Of course the Blitz already tries to help with this problem with testing scenarios for PBEM (or H2H) at H2H Productions and then posting these scenarios on the approved list (link at top of page in sticky post), the problem is that the bigger the scenario the more variables there are, add that to the time it takes to play/test scenario's of 60+ moves with "real life" always in the way makes any project like this very,very difficult but perhaps not impossible for a very dedicated team, hence i will not host a large scenario at the H2H.
So i wish you good luck with this, if you succeed it will be a great achievement IMO