Go ahead and write up the Hammerfell thing.
Put it out, see who'll join. It won't go by too quickly. Story can come in later. Maybe Haroun will actually show up himself if things get a little bad.
If it doesn't work write now, then you have the OP already written. Try something else, and do Hammerfell later if it doesn't work right off the bat.
I don't like the idea of creating a flunking roleplay and rehashing it later. If it comes out it should be epic and meant to go for the kill. It should be by all accounts, pure win.
Whatever you decide to do Immortal, please take your time and release it when you feel its just right.
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I would like to see whats going on with Cyrodil, I'd like to see some hope in the future and hopefully an explanation of why they seem to be getting bullied around by everyone. Maybe a hero can rise from their ranks and begin peacing their culture and country back together.
And a Morrowind Roleplay, concerning each faction's view on how Morrowind is best suited and their attempts to pursue that way. Of course these are ideas being muttered out, and it would seem that roleplays based on random ideas don't farewell. Although I see no reason why these can't thrive if given proper effort and thought.