The Capri 22 is a very light hull, and it carries a lot of weight aft. You have the outboard mounted on the transom, and the fuel locker both at the very aft end of the boat. The helmsman typically sits aft of the traveler, which put that weight in the aft quarter also. The result is that the stern tends to "squat down" in the water. For performance, you will want to move weight forward - my crew often sits just aft of the shrouds once the sails are trimmed, and will move to the cockpit only when necessary to sail the boat.
If your sailing single-handed, there is not a lot you can do unless you are sailing with an autopilot. Helming the boat from in front of the traveler/mainsheet is difficult.
On my boat, the battery (I use a single group 24 battery which may not be enough for your needs) is located directly behind the cooler/companionway step, as far forward as I can get it while keeping it on the centerline.