i've had a dragon goby for about a month now, SG =1.005. plants that seem to be doing well are bacopa, anacharis, java fern, and large vals (his favorite - he likes to stick to the side of the aquarium and pretend to be a giant val leaf). in fact the vals are sending out "runners" after a period of time when i thought they were dying off. i have a banana plant in there too but the jury is still out on that one. my dragon really likes having plants to swim around in dig at the bases of them, IMHO it is worth having live ones if you can keep them that way.
as far as eating - i'm still trying to find tankmates for him that won't snarf all his food. the way i know mine is eating is because i see him eat (like a hoover vacuum on the bloodworms and brineshrimp - like cookie monster with sinking wafers), and also because his food disappears and well... there are no other fish in the tank LOL