I already wrote about the variants I would prefer (depending on player number) here: https://phuks.co/s/Diplomacy/11297
I'd be willing to GM next. Whether as a dedicated GM, or as a GM-player, would depend on the final number of players who want a re-match, and what variant they'd prefer.
One change I would do is week-long turns. The 2-3 days per turn felt a bit rushed, especially with players who didn't respond right away and/or had to be caught in IRC to squeeze a reply out of them.