Here are all the registry values (populated with their defaults) you can use to customize MTV.
Save the output below the line to a .reg file and then import it.
These values are read every time MTV is invoked so no need to reboot or restart explorer to pick up the changes.
If you come up with a cool combination, post it back here!
===================================
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MultitaskingView\AltTabViewhost]
"Grid_leftmargin"=dword:0000005A
"Grid_rightmargin"=dword:0000005A
"Grid_topmargin"=dword:00000028
"Grid_bottommargin"=dword:00000028
"Grid_adjacentspacing"=dword:00000009
"Grid_rowspacing"=dword:0000000A
"Thumbnail_min_width"=dword:0000004B
"Thumbnail_min_height_percent"=dword:0000000F
"Thumbnail_max_height_percent"=dword:00000028
"Thumbnail_max_aspectratio"=dword:00000096
"Thumbnail_icon_size"=dword:0000001E
"Thumbnail_icon_plate"=dword:00000018
"Thumbnail_label_leftmargin"=dword:00000005
"Thumbnail_label_rightmargin"=dword:00000005
"Thumbnail_label_topmargin"=dword:00000000
"Thumbnail_label_bottommargin"=dword:00000000
"Thumbnail_hover_leftmargin"=dword:0000005
"Thumbnail_hover_rightmargin"=dword:00000005
"Thumbnail_hover_topmargin"=dword:00000005
"Thumbnail_hover_bottommargin"=dword:00000005
"Thumbnail_icon_leftmargin"=dword:00000000
"Thumbnail_icon_rightmargin"=dword:00000005
"Thumbnail_icon_topmargin"=dword:00000005
"Thumbnail_icon_bottommargin"=dword:00000000
"Thumbnail_hover_color"=dword:00000000
"Thumbnail_hover_percent"=dword:00000036
"Thumbnail_focus_border_width"=dword:00000002
"Thumbnail_focus_border_color"=dword:00FFFFFF
"Thumbnail_focus_percent"=dword:00000064
"Thumbnail_mousedown_shrinkpercent"=dword:0000005F
"Thumbnail_closebutton__width"=dword:0000001E
"Thumbnail_closebutton__height"=dword:0000001E
"ScrollButtonContainer_leftmargin"=dword:00000000
"ScrollButtonContainer_rightmargin"=dword:00000000
"ScrollButtonContainer_topmargin"=dword:00000000
"ScrollButtonContainer_bottommargin"=dword:00000000
"ScrollButtonContainer_buttonspacing"=dword:0000000F
"ScrollButtonContainer_button__width"=dword:00000069
"ScrollButtonContainer_button__height"=dword:00000028
"Desktop_background_margin_leftmargin"=dword:00000000
"Desktop_background_margin_rightmargin"=dword:00000000
"Desktop_background_margin_topmargin"=dword:00000014
"Desktop_background_margin_bottommargin"=dword:0000000
"Desktop_background_color"=dword:001D1D1D
"Desktop_layout_margin_leftmargin"=dword:0000000A
"Desktop_layout_margin_rightmargin"=dword:0000000A
"Desktop_layout_margin_topmargin"=dword:00000000
"Desktop_layout_margin_bottommargin"=dword:0000000F
"Desktop_item_spacing"=dword:0000000A
"Desktop_click_scale"=dword:0000005F
"Desktop_rest_overlay_alpha"=dword:0000008A
"New_button_glyph_size"=dword:0000000C
"New_button_plate"=dword:0000000C
"New_button_plate_hover"=dword:00121212
"New_button_glyph_color"=dword:00FFFFFF
"New_button_focus_margins_leftmargin"=dword:00000010
"New_button_focus_margins_rightmargin"=dword:00000010
"New_button_focus_margins_topmargin"=dword:00000010
"New_button_focus_margins_bottommargin"=dword:00000010
"Desktop_closebutton__width"=dword:0000001E
"Desktop_closebutton__height"=dword:0000001E
"DimmingLayer_percent"=dword:00000023
"Wallpaper"=dword:00000001
"DimmingLayer_leftmargin"=dword:00000000
"DimmingLayer_rightmargin"=dword:00000000
"DimmingLayer_topmargin"=dword:00000000
"DimmingLayer_bottommargin"=dword:00000000
"Grid_Desktop_margin"=dword:000000F
"Desktop_height"=dword:00000078
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MultitaskingView\AllUpView]
"Grid_leftmargin"=dword:0000005A
"Grid_rightmargin"=dword:0000005A
"Grid_topmargin"=dword:00000028
"Grid_bottommargin"=dword:00000028
"Grid_adjacentspacing"=dword:00000009
"Grid_rowspacing"=dword:0000000A
"Thumbnail_min_width"=dword:0000004B
"Thumbnail_min_height_percent"=dword:0000000F
"Thumbnail_max_height_percent"=dword:00000028
"Thumbnail_max_aspectratio"=dword:00000096
"Thumbnail_icon_size"=dword:0000001E
"Thumbnail_icon_plate"=dword:00000018
"Thumbnail_label_leftmargin"=dword:00000005
"Thumbnail_label_rightmargin"=dword:00000005
"Thumbnail_label_topmargin"=dword:00000000
"Thumbnail_label_bottommargin"=dword:00000000
"Thumbnail_hover_leftmargin"=dword:0000005
"Thumbnail_hover_rightmargin"=dword:00000005
"Thumbnail_hover_topmargin"=dword:00000005
"Thumbnail_hover_bottommargin"=dword:00000005
"Thumbnail_icon_leftmargin"=dword:00000000
"Thumbnail_icon_rightmargin"=dword:00000005
"Thumbnail_icon_topmargin"=dword:00000005
"Thumbnail_icon_bottommargin"=dword:00000000
"Thumbnail_hover_color"=dword:00000000
"Thumbnail_hover_percent"=dword:00000036
"Thumbnail_focus_border_width"=dword:00000002
"Thumbnail_focus_border_color"=dword:00FFFFFF
"Thumbnail_focus_percent"=dword:00000064
"Thumbnail_mousedown_shrinkpercent"=dword:0000005F
"Thumbnail_closebutton__width"=dword:0000001E
"Thumbnail_closebutton__height"=dword:0000001E
"ScrollButtonContainer_leftmargin"=dword:00000000
"ScrollButtonContainer_rightmargin"=dword:00000000
"ScrollButtonContainer_topmargin"=dword:00000000
"ScrollButtonContainer_bottommargin"=dword:00000000
"ScrollButtonContainer_buttonspacing"=dword:0000000F
"ScrollButtonContainer_button__width"=dword:00000069
"ScrollButtonContainer_button__height"=dword:00000028
"Desktop_background_margin_leftmargin"=dword:00000000
"Desktop_background_margin_rightmargin"=dword:00000000
"Desktop_background_margin_topmargin"=dword:00000014
"Desktop_background_margin_bottommargin"=dword:0000000
"Desktop_background_color"=dword:001D1D1D
"Desktop_layout_margin_leftmargin"=dword:0000000A
"Desktop_layout_margin_rightmargin"=dword:0000000A
"Desktop_layout_margin_topmargin"=dword:00000000
"Desktop_layout_margin_bottommargin"=dword:0000000F
"Desktop_item_spacing"=dword:0000000A
"Desktop_click_scale"=dword:0000005F
"Desktop_rest_overlay_alpha"=dword:0000008A
"New_button_glyph_size"=dword:0000000C
"New_button_plate"=dword:0000000C
"New_button_plate_hover"=dword:00121212
"New_button_glyph_color"=dword:00FFFFFF
"New_button_focus_margins_leftmargin"=dword:00000010
"New_button_focus_margins_rightmargin"=dword:00000010
"New_button_focus_margins_topmargin"=dword:00000010
"New_button_focus_margins_bottommargin"=dword:00000010
"Desktop_closebutton__width"=dword:0000001E
"Desktop_closebutton__height"=dword:0000001E
"DimmingLayer_percent"=dword:00000023
"Wallpaper"=dword:00000001
"DimmingLayer_leftmargin"=dword:00000000
"DimmingLayer_rightmargin"=dword:00000000
"DimmingLayer_topmargin"=dword:00000000
"DimmingLayer_bottommargin"=dword:00000000
"Grid_Desktop_margin"=dword:000000F
"Desktop_height"=dword:00000078
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MultitaskingView\SnapAssistView]
"Grid_leftmargin"=dword:0000005A
"Grid_rightmargin"=dword:0000005A
"Grid_topmargin"=dword:00000028
"Grid_bottommargin"=dword:00000028
"Grid_adjacentspacing"=dword:00000009
"Grid_rowspacing"=dword:0000000A
"Thumbnail_min_width"=dword:0000004B
"Thumbnail_min_height_percent"=dword:0000000F
"Thumbnail_max_height_percent"=dword:00000028
"Thumbnail_max_aspectratio"=dword:00000096
"Thumbnail_icon_size"=dword:0000001E
"Thumbnail_icon_plate"=dword:00000018
"Thumbnail_label_leftmargin"=dword:00000005
"Thumbnail_label_rightmargin"=dword:00000005
"Thumbnail_label_topmargin"=dword:00000000
"Thumbnail_label_bottommargin"=dword:00000000
"Thumbnail_hover_leftmargin"=dword:0000005
"Thumbnail_hover_rightmargin"=dword:00000005
"Thumbnail_hover_topmargin"=dword:00000005
"Thumbnail_hover_bottommargin"=dword:00000005
"Thumbnail_icon_leftmargin"=dword:00000000
"Thumbnail_icon_rightmargin"=dword:00000005
"Thumbnail_icon_topmargin"=dword:00000005
"Thumbnail_icon_bottommargin"=dword:00000000
"Thumbnail_hover_color"=dword:00000000
"Thumbnail_hover_percent"=dword:00000036
"Thumbnail_focus_border_width"=dword:00000002
"Thumbnail_focus_border_color"=dword:00FFFFFF
"Thumbnail_focus_percent"=dword:00000064
"Thumbnail_mousedown_shrinkpercent"=dword:0000005F
"Thumbnail_closebutton__width"=dword:0000001E
"Thumbnail_closebutton__height"=dword:0000001E
"ScrollButtonContainer_leftmargin"=dword:00000000
"ScrollButtonContainer_rightmargin"=dword:00000000
"ScrollButtonContainer_topmargin"=dword:00000000
"ScrollButtonContainer_bottommargin"=dword:00000000
"ScrollButtonContainer_buttonspacing"=dword:0000000F
"ScrollButtonContainer_button__width"=dword:00000069
"ScrollButtonContainer_button__height"=dword:00000028
"Desktop_background_margin_leftmargin"=dword:00000000
"Desktop_background_margin_rightmargin"=dword:00000000
"Desktop_background_margin_topmargin"=dword:00000014
"Desktop_background_margin_bottommargin"=dword:0000000
"Desktop_background_color"=dword:001D1D1D
"Desktop_layout_margin_leftmargin"=dword:0000000A
"Desktop_layout_margin_rightmargin"=dword:0000000A
"Desktop_layout_margin_topmargin"=dword:00000000
"Desktop_layout_margin_bottommargin"=dword:0000000F
"Desktop_item_spacing"=dword:0000000A
"Desktop_click_scale"=dword:0000005F
"Desktop_rest_overlay_alpha"=dword:0000008A
"New_button_glyph_size"=dword:0000000C
"New_button_plate"=dword:0000000C
"New_button_plate_hover"=dword:00121212
"New_button_glyph_color"=dword:00FFFFFF
"New_button_focus_margins_leftmargin"=dword:00000010
"New_button_focus_margins_rightmargin"=dword:00000010
"New_button_focus_margins_topmargin"=dword:00000010
"New_button_focus_margins_bottommargin"=dword:00000010
"Desktop_closebutton__width"=dword:0000001E
"Desktop_closebutton__height"=dword:0000001E
"DimmingLayer_percent"=dword:00000023
"Wallpaper"=dword:00000001
"DimmingLayer_leftmargin"=dword:00000000
"DimmingLayer_rightmargin"=dword:00000000
"DimmingLayer_topmargin"=dword:00000000
"DimmingLayer_bottommargin"=dword:00000000
"Grid_Desktop_margin"=dword:000000F
"Desktop_height"=dword:00000078