Not really, anyone who can model good enough to make a plausible ship replacement has probably made their own race instead.   If you're not afraid of some do it yourself though you might checkout some of the models the new factions in the Maelstrom mod, they are basically rearranged pieces of Sins ships.

There are particle replacement mods though.

The big ones do stay up to date, and a good chunk of mini dumps with mods are do to the fact you need to lower you graphics settings to avoid hitting the 2GB RAM limit. If you do that the good ones will be fairly stable. And I was suggesting that for your personal use you could take a model from a mod and replace one of the ships you don't like.