It's important after any music training to doodle. Don't try and apply theory, just doodle. Make stuff up. Wander around the keyboard. Hum along. I think that helps keep the creativity flowing and you can use the theory to solve problems, not write a song.
I have a habit of boxing myself into a corner with chord and key changes and what little theory I know helps me get my ***** out and back to the main theme.
As mentioned above, someone I know really well is top notch in theory and sight reading. But playing to even a metronome is nearly impossible because that unnamed person wants to constantly stop and replay any bad notes.
If you do have a chance to play with others, take it. That goes a long way.