need a little more info.
If you are diving a steel backplate and a wetsuit, you might find the HP100 to be a bit heavy, and might want to consider an aluminum 100 instead.
When I first got my HP100s, I dove them as singles, and with my 6lb backplate and a 30lb wing, I needed my wing fully inflated just to keep my head above water (and I am about your size). This hasn't been a problem since switching to a drysuit though (and I dive them as doubles now anyway).
Another thing to consider is the place you are getting your airfills. A lot of places will overfill your tanks giving you a few hundred pounds extra, however, at a lot of places, their bank is 3500psi, so overfilling high pressure tanks is not really an option (unless you engage the booster, which takes more time). My point is that with low or medium pressure tanks, you might be able to get better fills.
Lastly, at <24 dives, I would expect your SAC rate to drop significantly in the next 25 or so dives as you get more comfortable in the water, but you might want to check the SAC rates of the other divers you commonly dive with and try to match up so that nobody ends up being the one that has to call the dive all the time.