Great looking tank. You said you tried many types of plants, but what you have now seems to be thriving. Do you Have a list of what's in there now? Are you using the stock plastic lid with the glass strip ?
I did both, trimmed the 30", used the plastic light shell on top of the glass top:
Don't really have a complete list of what is in there, lots of crypt, anubias, mosses, h.japan, ludwigia, Hygrophilia corymbosa 'angustifolia' and Hygrophilia corymbosa 'Siamensis', who knows what else!
This tank is no more, at least at my house! Turned into a chore that I don't have time for rather than an enjoyable hobby. Maybe there will be another tank at some future date, but this one was RAOK'd as a whole unit (plants, fish, everything!) to someone local who came and picked it all up. Hope it does well there!