Great tank shape.
UG will give more head ache than HG ever would.
Monte Carlo might be fun.
Moss stones or Mini pellia etc in various spots with some other bright green plant would look nice and make the wood to appear to creep out from the main log.
You'd need a few smaller 3-5" cm dia branches, maybe 20-30cm long. Use cotton 100% thread and rope the moss on the wood, The ends will go back into the bushes, and the tips will poke out downward in the foreground. Then fill the space in between with Rotala green, Monte Carlo, Downoi, Hygro araguaia etc,