The ATA says singles targets are usually broken at 33-36 yards. I'd pattern in that range with my loads of choice. And as long as I'm using the board, I'd skooch my fit around until I had about 60% of the pattern above POA or maybe 65%. Trap targets are always rising and a high shooting gun will help.
As for smokeballs, they indicate excess tightness. If you're getting smoke on half your hits, go to the next choke you have that's a little more open. Like, LM instead of modified.
Or,stay with the tighter choke and smoke them, accepting you're losing a few targets but learning to center them better.
HTH....