I would get away from the canister as like your finding out they cause issues ,
I would suggest going with a nice sized sump 55g , it would give you room for a nice skimmer your pumps heater ect , you can build baffles to make sections ,
maybe build a nice algae scrubber you can do many things in a sump that size
I myself have a basic sump no baffles it's a wet dry setup with a algae scrubber . I use 2 skimmers and a phos reactor . I keep rubble rock and macro's in the remainder of sump
just a simple set up . I keep saying I want to upgrade but I have yet to do it.