Been playing this game a long time with multiple boats at a time and this is what I've learned FWIW;
Heat kills electrical devices.
More banks equals more heat concentrated in one spot.
I use a single bank and a 2 bank in my 3 battery boats, and two 2 banks in my 4 battery boats.
These setups cost no more than 3 and 4 bank chargers.
If you do happen to lose a bank, I'd rather toss a 1 or 2 bank in the trash than a 3 or 4.
If it's a repairable Dual Pro, I'd rather wrestle a 1 or 2 bank out and back in the bilge than a 3 or 4 bank, and pay less to ship it, not to mention I still have a charger in the boat that will allow me to make do until I repair or replace the bad one.
Grew up on Tawakoni and Texoma before hybrids and stripers existed on either.