Yeah I gotta agree with you Brooksta

Oi, if you enjoyed being in the surf a few times on an 11 foot SUP, then why not stay with that size? What made you think it was too big? What sort of waves will you be going out in mostly?
I personally think that you can never out grow a SUP board.
Maybe the proper term would be that you would want to change your style?
All boards with different lengths and widths deliver different styles. They paddle, glide, turn, balance and surf differently.
Im 65kgs and I ride a Starboard 11'2. Ive been riding this board for over 14 months now and will never out grow it.
You will find this board will help you learn the SUP technique and you will definately be able to surf this board.