I know here is allready an idea or request for making some modifiers multi-threaded. But I honestly think thats not enough!
Please make EVERYTHING in 3dsmax multi-threaded - NO EXCLUSIONS - this is urgent and shoud have happend long ago!
My personal priority list:
1. MaxScript execution
2. Animation Controllers and Curve/DopeSheet Editors
3. Modifiers
4. PFlow
5. Anything else
If there is something that couldn't be made multi-threaded, kick it out!