Iron Heroes multiclassing

[Aroka]

I'm new to Iron Heroes, and the game really gives me a sense of wanting you to stick to one class; for one thing, multiclassing seems to be a sure way to lose Mastery levels (although it also seems to be one of the few ways to get Mastery 10; after ~17 levels of your class, add 3 in man-at-arms and you'll get 10 in your main Mastery).

And with all those abilities to keep track of and advance and actually use, it seems like keeping track of multiple classes' abilities and even more token pools could be a chore.

Does anybody have any multiclassing tips? Classes that synergise well? Ways to avoid mastery level loss? Good houserules to balance out any problems?

[Gametime]

The Iron Heroes classes seem, in general, less friendly to multiclassing than their martial 3.5 counterparts. The obvious exception is the Man-at-Arms, who obviously make an excellent dip for anyone. A few levels in Thief or Harrier could probably benefit a lot of builds, too.

For the most part, though, the token-based classes reward sticking with it.