Ours isn't too high really but there are some high ones out there. We got Disney cars lightening queen double duvet set, nothing much in shops but loads on line. Also put 3 pillows, 2 small adult ones at each side and his toddler one in the middle so it kind of feels cosier.
DS1 been in it about 6 months now, his mates think it's great he's got a big bed lol.