Hi
"Oh, and Dev Team: wouldn't the blending mode be a cool feature to have in VP?"
I agree. This would be a useful addition to the features already incorporated in the VP effects.
For manipulating images I use an old program ; MicrografX Picture Publisher.(PP) It's no longer available but has many of the features that Photoshop has.
The "Blending" option in this program (PP) is the Merge function, and can be applied where two or more images are pasted as objects one overlapping the other.
This is analogous to having a video Track 1 image/clip and a Video Track 2 image/clip laid over it.
In Picture Publisher the merge functions that can be used are...
Normal...........Top image overlays the lower
Additive
Subtractive
If Lighter
If Darker
Filter
Multiply
Difference
Texturize
Color
Hue
Saturation
Luminence
Red
Green
Blue
Invert.
Here are some examples of image overlap. With one of the "Objects" - the top one, selected The Merge Mode becomes active and the down arrow has been clicked to reveal the menu of options.

Above is a screenshot from PP showing two images with a Normal Merge. The top image (or object) overlaps and covers the lower..the same as with VP.Track2 covering Track1. (Only a part is covered for clarity)
Some of the list of Merge modes can be seen in the small drop down menu with "Normal" selected.

This screenshot from PP shows the effect of merging by "Addition" where the brightness of pixels in both images is added together.

...And This screenshot shows the effect of inverting the colors in the overlapping area... and so on....
Without being too optimistic I can see in my mind the various options incorporated into a "Merge" effect window with labelled tick boxes similar to those used already in the "Old Film" effect window or as a drop down menu as in PP.
What is the possiblility of doing this?
Nat