Good set up and a beautiful betta. I would suggest taller plants and a hiding place i.e.coconut cave or something the betta could swim in and out in.
I would also suggest a plant like the Elodea Densa, 5 or 6 in there, Bettas like to rest and hide in them. Pretty cheap, you can pick them up on ebay for a few quid.
Other than that, fab set up