Lisa, no worries about asking "too many questions" about your trailer! The time to ask is before you do the build & installation, not after. Everyone here is pulling for you & will help when they can.
If you locate the battery in the galley, it will take up quite a bit of valuable real-estate inside the build, there's just no way around that compromise. Mine was done because I have a tongue box which came with the trailer (a 50# beast of a steel box), a 35# air conditioner to mount in the front at the headboard, the propane tank on the tongue & stuff stored in the tongue box as well. That's over 100# of stuff adding to the weight at the hitch, so I chose to put the battery in the galley for ballast, once I ran the numbers for balance & tongue weight. I'm still concerned with weight, balance & trim on the road, but I'll adjust things with stowage when the time comes if necessary, so for now I'm living with the choices I've made.
Remember, depending on the tow vehicle's capacity, you want to have a minimum of about 10%-15% of the total trailer weight resting on the hitch ball. Any less than that and at freeway speeds, the trailer can get too "frisky" (tail wagging the dog syndrome), especially in high winds, with trucks passing, etc. Unfortunately, it's one of those things where the more you read, the less you know. Just keep moving forward & things will get done. tim