I see many reasons and purposes for the belly pan. Regardless of where you live, it probably rains there sooner or later. Without the belly pan, water on the drive belt can cause slippage which is sensed and will turn off the air conditioner. Even if you don't need the air conditioner, slippage is not healthy for the drive belt.
It is worth keeping it on. You may have to keep a handful of the captive nuts handy, and maybe add a little tension to keep them from popping out. You know, bend them a little.