If it was me, I'd purchase a 140 or 150, then take the 110 to a sailmaker and have it restitched, just in case you want to hoist it for stronger wind days. Always nice to have few sails in the locker. There are some interesting articles on improving headsail changes with hank on sails. The main thing is to attach separate sheets, instead of one long sheet, doubled and cowhitched at the clew.... that way when you change sails you don't have to re run the sheets. It also means you won't be tempted to stuff your sheets in the bag with the sail, which is bad for both.
One interesting tip I came across was to fold the sail so the luff was in line and the hanks could be clipped to a short wire pennant with snaps on each end. If you have two halyards, the new sail can be attached to the new halyard and tack fitting, the hanks still held captive by its pennant. The old sail is dropped and the hanks transferred to its pennant and the sheet is transferred to the new sail. As the new sail is hoisted the crew clips the hanks from the pennant to the headstay... The old sail can be rolled/folded and then bagged with the hanks in position for their next change. The pennant system is an especially good technique in difficult conditions or at night because both sails remain under control at all times.
Regarding your sail plan strategy, I'd determine the headsail choice based on anticipated wind conditions....I tend to start out with the smaller headsail if I'm at all unsure which way things are going... the thinking is it's easier to upsize in quieter conditions that it is to downsize in mounting weather. So... if the wind is 12 kts or so... I'll start with the 110, allowing me to reef the main if things get busier and the boat starts to feel overpowered. If I'm feeling the 110 and full main aren't enough I can change to the 140... etc.
The final suggestion with hank-on sails is to rig a jib downhaul. It will give you a lot of confidence with your sail handling, knowing you can get the headsail down on just about any point of sail and keep it secured on deck, without having to go forward. On my C27 the jib downhaul is a small diameter (1/8") dacron line leading from a small cleat in the cockpit along the stanchions to a small block on or near the stemhead. The line is TIED to the top hank with a buntline hitch(tying it to the shackle will allow the head to fold over and possible bind the top hank in the headstay) . The line in NOT woven through the hanks, it simply flys free. Once the sail is pulled down, cleating the line will keep the sail from bobbing up and down when the boat is powering out over waves.... which, in turn, will prevents any chance of the halyard getting fouled.
