Well the thing really capping GI right now is performance, if it’s not useable for a cross platform game then it’s not widely useable, and making everything else perform reasonably frees up more bandwidth/ALU’s/etc. for GI to take up. The implementation of DFAO/GI right now could definitely still use performance refactoring, but no matter how fast it gets it’ll still take up a lot to get looking good.
As for refactoring everything else, I would guess a lot of it will be the nitty gritty technical stuff that’s not terribly new and exciting, at least from a feature perspective.