I'm kinda in the same boat the battery set up I want would be about 2000 dollars and dollar for dollar it's about the same just a lot up front. Honestly I'll probably go the agm's and just be happy. Momma let me buy the new boat and want to upgrade batteries, it came with interstate 27s for free but wanted to charge me 300 a piece to upgrade to 31s I said I'll do it myself at that price.I'm no help
Last week I "looked" at buying 2 TLI-100 Lithium plus a new charger. My charger is only for wet/gel/agm batteries
I'm an old tightwad so instead of buying 2 of the TLI-100 lithium batteries that weigh 30lbs each I bought the 31 AGM batteries that weigh 65lbs each(I weighed them) from Sam's. Then I re-located them to the other side of the boat so the boat would not have "the lean"
On my boat they made it so the wiring run is on the drivers side, the 2 starting batteries are on the drivers side along with the trolling motor batteries in the front. Plus me
Which some red-neck engineering and a hole saw I was able to move the front heavy batteries to the passenger side .
It road pretty level today on the river, for once...
Just curious why do you have 2 starting batteries?
How was the fishing? I'm itching to get back out but the weekend temps might keep me home. 35 for a day time temp doesn't sound fun right now