Thank you very much for all your comments. As you have said, I think I made a mistake by buying based on other people reviews, and I'm trying to tell myself that it's me, not the speakers.
I can still return them (in NL you have 14 days) and I'm afraid that's the right decision here. I could replace my receiver but I don't want to spend more money at this moment (and, in the future, I'll prefer to put the money in a sub).
Just for the record, after 10 days the treble of the MA is smooth and detailed, but the bass is still missing. Whether it's because of the speakers, the amp or the room, I can't know. They're very dynamic and detailed but the sound lacks body. When I run the auto EQ (YPAO), things get better (highs are cut and bass is boosted), but I don't see the point on investing on new speakers that you have to equalize severely to enjoy them.
With this budget in NL I can find QAcoustic 3050 and Dali Zensor 7. Can you share your thoughts about them? How do they compare to the Bronze 5? Do you have any other suggestions? Don't get me wrong: I won't buy without listening; it's just to pick a number of candidates. I listen to virtually any kind of music and movies. My preference will be to have the more detailed voices (I don't need the crispier highs or the deeper bass, but I think that an unbalanced system will never offer proper mids though).
Again, thank you all for your time.