I will make one comment that seems "too obvious"
If the plane is going too fast at your "normal" throttle stick position, pull it back a little bit.


I do not move the throttle much while flying and occasionally wonder why it's going so fast (or slow); and it takes a while for it to register that I can control that.


But, don't be afraid to change props. If you put on a lower pitched prop, the plane will not fall out of the air. You might find yourself at full throttle all the time and wanting to switch back. If so, just land and make the swap. The MA 12x4 and 12x5 props are about 4 dollars each. If you have a LHS (and if they have them in stock) you can try both for about 10 dollars including tax.