HC, dwarf hairgrass, glosso would all look good in the foreground, a small anubia would look good nestle'd in that little dip in the wood between the rocks, HM sounds good for stems, or you could use micranthemum umbrosum, i wouldnt overcomplicate the background, maybe some crypt parva around the base of the wood/rocks in the gaps? i dunno if i like the idea of e tennelus in a tank that small, might work if its round the rocks/wood and the forground was hair grass