A general list of our changes to TinyGL is available here: https://raw.githubusercontent.com/resid ... /Changelog
As for speed, I'm not really sure, we have tuned it a bit last summer, but in practice it's not really fast.
Not really sure about the CLUT-8bit thing you're talking about either, could you perhaps tell us what you want it for?
I think we added something to the blending capabilities (IIRC it only supported 1 bit alpha originally), but it won't be fast.
For a quake-fork you're probably better of using whatever exisiting trickery was added by id in the original software renderer they had,
we're not getting the best of results out of TinyGL as it is, and we're not really rendering that many polygons at all. (Feel free to download i.e. the Escape
From Monkey Island demo to see what we're talking about, that has way more polygons than Grim Fandango, and is playable, but also 2.5D whereas
Quake would be full 3D.)