Memory Pool System by Ravenbrook

Very general, very good, but very intrusive. I would use it for a new language VM, like a lisp.

But putting it on top of an existing large library is probably overkill. Much better than the simple BoehmGC though. This is the real, fast, generational, copying GC. Probably better than the best Java GC's.

Yes, it would have value in a game engine once you hit the point of having bigger memory management needs. Has a bunch of customised allocators for different kind of data that you can use to enable good performance patterns in your code.