I need variety in pacing, and part of that means slowing down. I find games that just stack one action mission on top of the next boring and tiresome. Shooters do this a lot, but so do other games. Granted, "boredom" is a subjective thing, and other people love this constant-action style. I find constant action boring, though. It's like listening to a singer who has no range, who can only sing in one key. I prefer a mixed pace, where fast alternates with slow, action with reflection/dialog, outer with inner.
However, the slower parts should be worthwhile; they should be interesting and engaging on their own. What OP is complaining about, if I understand correctly, is slow moments that are just dull and mundane. I agree with that. If you're going to make a slow sequence, make it interesting - something introspective, some quality dialog between characters, some world exposition.