Well, while you are technically correct that Munich malt is a base malt, it produces an intensely malty flavor that I found to be overwhelming when competing with hops and bittering. The example of Dusseldorf Alt comes to mind. That is an intensely bittered ale, often with high malt character that is often derived from munich malt. Even Sticke versions that are dry hopped tend to have modest hop character that is still generally dominated by the malt flavor.
Adequate sulfate in the brewing water does help dry the finish, but if you still don't produce the hop-centric flavor you want in that APA, I think you will find that backing off the munich and crystal is likely to help.