I’m doubtful anyone involved wants to tackle more document-originated tasks 
hence suggesting a funding request
I think we need to do more than just document everything together in one place. Part of the premise of creating another Whitepaper is indirect marketing. We want more eyes on Grin/ new contributors. If we just put together some document then it’s only likely to get viewed by those already involved in the project(small audience) however, a new MWv2 Whitepaper is likely to get picked up by news outlets eg CoinDesk, thus gain more interest/ be seen by a much larger audience.
If we created a new whitepaper with future research questions —> after the whitepaper has done the rounds and gained some attention we could then run bounties for some of the questions( eg new security proof for two-step method/ trustless aggregator- which could be at the protocol level), I’m sure many would also like to draw more attention to the protocol level NIT schemes. I also don’t see a big issue in including potential implementation details in a section of the paper 