Day convert will throw things out of whack for the cult. It's too sudden and doesn't give the converted player enough time to adjust before having to post again in the thread. Can lead to them easily getting outed if they slip up. With lynches being the only kill, the game could run for too long, growing boring and tiresome as a result. 15-minute day phases are also too long as evident by the dislike for it in the Give me the gun games.
2 mafia vs 1 cult leader vs 8 townies. Maybe have an x-shot doctor to protect against the conversion and kill. Cult leader's conversions are a 2-shot. Cultists don't inherit any converts if the cult leader dies. Conversions fails on mafia. Converts don't show up in the write-up, be it successful or failed. Failed kills shouldn't show up either.
10-minute day phases, 7-minute night phases.