I saw the first two seasons only.
Sometimes Reid is just... too intelligent. I remember when he had to discover a password and he deduced it had to be the title of a song from a cd that was inserted on a disk drive, and he was correct!
But you are right, Reid need more "Reid-centric" episodes. In a lot of chapters he has only a few lines and doesn't interact with the group. Gideon, Hotch and Elle interact a lot, same with Morgan and Garcia, but... Reid? So yes, he needs to be the protagonist of some episodes because his interactions with the group don't reveal a lot of information about him.
Maybe this has changed now, I don't know, I have seen only the first two seasons.
My favourite character is Gideon, he is very intelligent and kind and he has a great voice and good taste in music.
I loved Gideon to! I was so sad when he left. The show is not nearly as good now.