Wow, that's a lot. Taking it one at a time.

"1. COM chews up a lot of memory and pegs the CPU. "

.COM is known to be a hog but it shouldn't be that bad though. .COM is known to do that if asked to do to much at once. What is your program trying to do when the CPU pegs? I think your other perfomance issues might be related to this one.

does Windows had a 'nice' equivalent for COM?"

Yes .NET, but it's an incremental improvement only.

I have been experimenting with:
Win32::OLE->FreeUnusedLibraries();
Win32::OLE->SpinMessageLoop(); sleep 5;

This is sure to cause more problems at this point. Better to find out what's causing the original problem and fix that. The FreeUnusedLibraries hack still can take time to deallocate all the modules and will only cause things to run more slowly if you are not truely done with everything.

As to the other problems you mention; my ESP powers tell me they are related to .COM getting behind with what your telling it to do. This might or might not be the case if my ESP is faulty.

Did you know the debugger from the .NET SDK can be used on .COM objects?