@hbrock and @xgalaxy, now that public overall roadmap is up, I’ll try to get trello board for Paper2D up.
There are a number of serial dependencies I need to work thru first before others can just jump in without ground shifting out from underneath them. After that, it will be much easier to grab work from ‘nice to have list’ or improve what is there, especially adding features to sprite editor, etc…
I’m currently focused on core bits that are necessary to even consider using Paper2D in a game (namely efficient rendering support with automatic atlas generation and batching).
@ssfulfe, 2d textured splines is already on my radar, though I haven’t seen Ferr2DTerrain before, which seems to go a bit beyond it (slope detection changing border texture / etc…). I’d love to have features like that, but fundamentals come first 
I think UbiArt does a similar system for their platforms and terrain as well.
Cheers,