One arming the spin is a lot of work! You get used to it over time. But, as the wind picks up, you probably need to sail a little deeper.
In light air it is easy to over sheet. Be sure that is not happening. On my boat, if I ease the main sheet, the traveler drops down just a tad.
At 220 lbs., I try to move forward as much as the air will permit. I think weight distribution should be a priority.
I hope other, better, sailors will offer advice.
btw- I was advised by a sailor on another boat that I was probably sailing too high under spin this past weekend. It's exhilirating, but like all things, you can over do it.