Having spent some recent time on a small sailer, I think I can help a little. I use the mainsheet like a throttle, pull it tighter, up to where the tell tales on the outside stall, to go faster, and ease it off to slow down.
I've sailed with the seat of my pants wet, even on a laser, (no keel
just a dagger board), I've also flipped it.
A keel boat takes a lot to turtle, I just looked up your boat, 1000lbs ballast in twin keels, 2200lbs displacement
I don't think that boat is going over in less than a full gale. The twin keels may make it a little tender
at first, but like a weeble, "it may wobble, but it won't fall down".
Seriously, I would look into making some kind of reefing system, even rolling the main around the boom, (that's how mine works), you just need an outhaul attached somewhere. 1 reef will tame even a blustery day, and it shortens the learning
curve, you can always shake it out later if you want more excitement.