What is your water like Vic? IS is nice soft South American type water or rock hard African rift lake water or something in between like mine? That will determine which cichlids would be your better choice for minimizing water problems and extensive water manipulations. Since you are already aware, as an experienced fish keeper, that mostly what we do is maintain water and add some food now and then, I am sure you already realized that but being away for a while may have made you forget it for the moment.
For a 55 these days, you would be more likely to go with a canister than you might have some time back. It is all about flexibility of media really. The hang on back filters are quite limiting and the canisters are much more versatile.