so in my senior year, i have option to pick a music class. I picked guitar of course even though i will just learn beginner stuff anyway so it leave me with music theory and piano class. I dont know what i should pick, i really like to play piano but lot of ppl say music theory is important.

So what do you guys think? which class should i take?
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Dont take guitar if you wont learn anything new with it. Take both piano and theory, it will really help your overall musicianship.
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Well, my piano experience has never been limited to just, well, piano. Does the piano class have any theory in it?
Theory...most important IMO...if you will stay with guitar at least.
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Piano probably has theory in it, but Theory class will help you a hell of a lot more than piano class.

Theory class helps you a hell of a lot, well it helped me. Depends on how much effort you want to put into actually learning.

Your improvisation will definitely improve as well as solo writing ability, and when you write songs it'll also help you modulate keys rather than staying in a single key with 1 accidental every 4 minutes.