Some of the easiest ones I've worked with are Java ferns, Anubias, mosses, water wisteria, duckweed, contortion vals, and dwarf sag. They're all pretty easy and can be grown without additional fertilization or co2. Just give them some light in the 6500k range and you'll be good to go.
my anubias, anacharis, amazon swords, oriental sword, micro swords, and java ferns (among some other aquatic ferns easily found at pet and fish stores) all did great in my tank before i starting dosing ferts and stuff. very easy since it was my first live plants only tank. i also have a sword thats not an amazon sword, it most resembles a melon sword but i can't remember what it is. moneywort has been growing nicely for me, too.
I have some Green Hygro at the moment but it doesnt seem to be doing very well. Also have baby dwarf tears that I know will not carpet without CO2. Are these plants usually quite easy to grow?
I just have a hang on LED but the tank seems quite bright,