A ball bearing .46 will definitely provide more oomph but will weigh more and may require a rebalance for correct C of G. I'd try another prop first.

Get an APC 11 x4 and an APC 11x5 (and maybe an MA 11x5 and 11x6) prop and try those. They should provide more thrust than the 10 x6.

One of the guys at our field has an OS FP .40 in a trainer. He tried many different prop combos and ended up with the best overall performance running a Bolly 10.5 x 7 prop on his. It was far superior in thrust and speed to the MA 10 x 6 he started off with.