The dev fund idea's an interesting one. Having a portion of each block reward going to a certain address would require a hard fork, there's no way around that. But it wouldn't take much work.
It'd probably be best to use a multi-sig address controlled by a few team and trusted community members.
Block time: ~64 seconds
Blocks per day: ~1350
Dev fund stipend per block: 0.5 MOIN
This would give the fund about 675 MOIN per day and 246k per year. At current prices that's around $860. Admittedly, that's not going to pay for much development time, but I still think it's a good idea. To get us to a point where the fund's worth something substantial will require a decent amount of unpaid work, but it'd at least give us a better chance of achieving self-sustainable growth at some point in the future.
Dev fund sounds good, but it needs to be well managed (regulated).
Good example of such thing is ColossusXT. The devs manage funds very well with their platform.
Not familiar with Colossus XT but as far as I know Decred has the best governance in crypto. Anyone can make a proposal and the community can vote if they want proposal to pass. The money comes from the dev fund. This maybe a bit much for Moin right now.
Dev fund is not a bad idea but maybe keep it simple for now with only multisig until we see how well it's working.