I've been working on something pretty similar (although more audio/music focused) and just working on getting the display board built. I'm more of a software guy -- I have done a lot of work on Loboris's Micropython port to get it going with the FT813, including having the REPL & etc show on screen (this wasn't trivial-- the FT81X display list doesn't have enough space to show enough characters on its own) and a USB keyboard doing the input. I've also got the FT813 working with a bigger display, a 10.1" 1024x468 widescreen. I'm working with a friend to get the PCBs manufactured.
I think we could probably share notes at the least, check out my build log: http://tulip.computer/
Are you going to use crowdsupply again for the TROLL? Let us know, I'm excited for one!!