Remember, when you multi-class (especially at higher levels), there is the opportunity cost of what you could have gotten had you remained in your class. Most of the time, higher level class abilities are going to be much better than the first level class abilities (even though most classes are front loaded).
I have not yet seen this particular example occur, so I don't really know how much of a "problem" it really is. If you're especially worried about it, change rogue expertise to read "add 1+ 1/4 your Rouge level, rounded up." This mimics the standard proficiency, but limits the benefits for multi-classing.
I have not yet seen this particular example occur, so I don't really know how much of a "problem" it really is. If you're especially worried about it, change rogue expertise to read "add 1+ 1/4 your Rouge level, rounded up." This mimics the standard proficiency, but limits the benefits for multi-classing.