Loose footed, partial full batten (Ooops!)
I crafted the answer below before I realized that this is the guest expert forum! I value Tom and Bill and their support - they are the experts, so you can take my comments as the humble amateur opinion.DavidLady LilieTwo full battens at the top of the mainsail will allow your sailmaker to add more roach (sail area aft of the line from the head to the clew.) And they bring no negatives that we can see. The added roach can be limited by your backstay - the sailmaker should know the limits for your boat.Full battens on the lower half of the main offer fewer advantages (smoother shape, and control of flapping of the sail) and bring some issues. Special batten cars may be needed in the sail track, and the battens are awkward when putting the sail away. Serious racers often favor full battens, though.A loose foot means that the bottom of the sail attaches only at the clew and the tack. This gives simple and easily visible control of the lower part of the sail while making it easier to rig to the boom. The alternative is a shelf foot which has a bolt rope for the foot, but allows shaping with a "shelf" of fabric. The supposed advantage is that air cannot leak off the sail at the foot.Hope this helps - in any case, I recommend that you talk to a sailmaker from this site, or a local loft - they should be able to explain the options better than I did, and make recommendations that fit your needs. If they can't, then find one that can!