I'm generally a 2D guy like many wargamers. Not familiar with Tabletopia. I picked up Vassal because I wanted to be able to play a fantasy wargame, viewed some youtube videos on it and discovered it wasn't too different from creating web-based training programs (something I used to do for a living).
In vassal, you'd represent the pieces with flat counters, and when you mouse over them, it "zooms" the stack so you can see its contents. I suspect it takes less talent to produce something with Vassal though it won't be 3D. I personally find 2D easier to analyze ... for example watching a Chess game in 2D vs 3D, it's easier to identify everything in 2D. As an example, on a whim this weekend I threw together a Vassal module for "Trippples" and it took about 5 hours (8x8 board with some checkers, 4 translucent playing pieces and a set of 48 square tiles with all permutations of 3 arrows pointing in different directions).
https://boardgamegeek.com/video/264913/ ... les-review
I was thinking that I'd check out the Conquest tool and see if I could just throw in the graphics into Vassal, map the spaces so that you can generate logging messages as pieces move from one space to the next, and a few add-ons (e.g. a counter for moves left, shortcuts to remove captured pieces, marker to show where a capture occurred for signaling recapture).
All the best,
Tom