Because of the limited scope and limited demand niche coins are not used to stay afloat for a long time. Perhaps you want to take a look at the NXT monetary system. That's something designed for making such coins on the top of the NXT blockchain.
I think its best to stick as closely as possible to the original bitcoin source code, which has been proven to work and only make those modifications that are needed.
NXT is fairly buggy too and not well documented.