Let's see...
Sagittaria subulata, Cryptocoryne wendtii ('Green', 'Tropica' and 'Bronze/Red' varieties), Cryptocoryne spiralis, java fern, Anubias barteri 'Coffeefolia', Bacopa monnieri, Hydrocotyle leucocephala, Ludwigia repens, Hygrophila difformis, Rotala indica/rotundifolia
Pretty much all low to medium light plants.
Stock is still up in the air right now. Will be some time before any fish.
Definitely! I'm not a huge fan of the 55g because of how tall they are compared to their depth front to back, but can't beat having a 4 foot tank!