New to boat trailers … need some help

Personally I would just keep the surge and change over to 4 wheel disc. I can't even tell my boat is behind me in a stop. IMO you are looking for trouble having electrics repeatedly dunked. IMO the surge brakes are more reliable and consistent the only down fall (which you won't have a problem with) is they don't work in reverse. I've seen people putting big bass boats in with little cars and SUVs get dragged backwards down a steep slick ramp. I would leave the tires alone for now. You have plenty of capacity for your boat weight.