Re: PbP Interest Check
Personally I'm for the following:
Start ending stories quickly, but not quite "this is what happened" quickly. Get everyone ready to start the next day in 3-5 posts at most. Have the monsters automatically win/lose/flee if someone's in a combat, and then something ominous to force[1] them into the nearest building for the night.
Then start up a final climatic adventure for each person. But don't play it entirely out. Let them god-mode random encounters that they could easily win, RP'ing the entire fight from observation to victory[2]. If you're not sure which way it'll go, set a percentage chance and roll one die, though for non-planned encounters that shouldn't happen very often. Generally allow a few liberties in the strict-adherence-to-rules department in order to end the game quickly without stiffing the story. Just be explicit about when this will be allowed and to what extent. As people start finishing, put a rush on the rest so that (hopefully) almost everyone finishes within about 5-7 posts of the first few.
Then take a week or two off to make any adjustments it needs, and start up v2. Maybe give people who "won" v1 the opportunity to take an additional flaw/talent pair to recognize their experiences at the first gate, and/or some other minor benefit on a case by case basis[3].
[1]My suggestion for that would be the demonic influence of the gate taking hold of the fog I put up when I fled hell. Congealing into tentacles and mind-bending shapes and whatnot, snaking through some streets and leaving others empty, to explain people who already advanced to the final day and didn't see it.
[2]For example, Ashley sees in the distance... well just about anything. The chance of even a large party of demons damaging her when she's aware of them while they're 2 turns out of melee range is... remote. At this point it might be better to just RP it myself and present you with the MP/HP/PP/corruption cost, saving a good deal of effort on your part. Experience is probably pointless once the final adventure starts, since you won't be resting.
[3]Personally, I'd ask for the "mutations" flaw with a few of the more minor ones, the "experienced caster" talent, and the ability to do a few non-combat spells that nobody else knows. But we'll talk about that when the time comes, and assuming you do decide to give minor benefits to characters moved from DG1.