I've seen guys do a carpet of crypt wendtii before. A lot hardier and easier to grow than some other plants. Might grow a little taller than what your looking for though.Maybe tie plants to a rock and bury them in the substrate... I really wanted a carpet but I guess that's out of question lol
Given what your describing here what I personally would do is track down some potted plants. These will have more established roots already and will likely stay planted easier even with the fish disturbing them. For background plants I would be considering swords, crinums, crypt balansae and aponogetons. For the foreground crypt wendtii. You can always work in more anubias and java fern tied to rocks. Anubias that is planted with the rizome exposed can also be grown as a foreground plant.Iv just always wanted a dense planted tank and I also want to make maintenance easier to where hopefully I just need to do water changes and the carpet will take care of any waste... But I also don't wanna get rid of the fish I listed