Well, it depends on what your using it for, targets, or hunting ? for targets I would go with 45-50 spine and 125 gr. up front. For hunting you might want to try a heavier broad head and up the spine to 50-55 or 55-60 depending on the weight of the broad head.
I don't use wood due to time constraints, I have had good luck with Traditional GT's 1535's with 50gr. brass inserts and 125 gr. tips in my 48" Mag. and it is 45# at 28" ( I draw 26 1/2" ) I also use this set up all the way up to 50+ # in my other bows.
Good luck.