Keep experimenting, Each bow has its likes and dislikes.
I have a 50# at 29" recurve with a 6-strand SBD string that is shooting 29.5" 2117 with a 125 gr. head on a glue-on-glue-in insert. The bow seems to like that set up. I have found that fast-flight skinny strings do require a bit stiffer arrow than, say, a 14 strand string.
Every bow has its quirks. I am also shooting a 51# at 29"recurve that wants a 400 size carbon at 29.5" with 160 gr up front. That bow does not shoot the 2117 shafts well at all -- and it is only 1 pound draw different from the other recurve.
Keep experimenting, the bow will let you know what it likes.