Just my opinion from what I've experienced on my own boat without an elwctric trolling motor...
Keep one a starting or dual-purpose for trolling on the motor and running everything else while the motor is running and keep the deep cycle for the electric trolling motor. You have to draw the deep cycle down, I ruined 2 in 2 seasons by just running it trolling on the motor. The deep cycles eventually wouldn't hold a charge overnight to even run the bilge pump. I never drew them down enough.
As far as running everything on the deep cycle, do you really want to run your downriggers on it until they can't come up or your fishfinder quits from low voltage? If you operate on your motor with the deep cycle, you won't draw it down enough for the motor to not maintain a good charge.
Run the deep cycle for your electric trolling motor and whatever you run without the motor and keep a starting or dual-purpose for everything you run with the motor on.