Depends on what you want to be convenient to. If you rent a golf cart, location doesn't matter much as you can hop in the cart to get anywhere, and ride the cart to the boat docks or main bus pickup.
If you don't have a cart, and don't want to walk as much, you may want to pick one of the last 5 or first 5 cabin numbers in a given loop, which will put you close to the bus stops (though also closer to the main road, so you may hear more noise).
If you want to be close to the pool and laundry machines, 2700 and 2500 loops are on either side and closest to walk. Again, consider that if you're in the back of 2700 loop, it's a long walk just out of the loop, so you could technically be closer to the pool over in 2300 loop if you're right near the main road.
None of the loops are close to things like store, main pools, boat docks, etc. For those, you either take a bus, or again if you have a golf cart, no problem.
For walking to the main bus stop to head to the theme parks, 2800 loop is the shortest walk - you can always take the internal bus there, but some people like to walk.