>I will be the only developer. When distributed it may have any number of users (probably less than 50 though, if that makes a difference).
Based on what you said, having them on individual class libraries makes sense since they all seem to be different pieces of the puzzle.

On the other side, you may want to keep them all of them on the same VCX and be able to drag and drop a single VCX and not worry about dependencies.

As you can see, the right answer depends on a lot of factors. There is not a right or wrong genereric approach. It will depend on what you have and intent to do.

As far as COM is concerned (and the number of users) it really does not matter whether you store them in one or many VCXS. Your COM DLL (or EXE) will have them all in the same DLL (or EXE) regardless of how many VCXs you decided to have.