I have heard about the hiding spots and can attest to this, but don't agree with removing all the spots. I had a black rhom in a 40 and tried to keep it bare besides gravel, and was always somewhat bitter as the Rhoms are supposed to be so aggressive but my guy would just turn and swim into the corner whenever I got in.
So I gave in and got a nasty fake plant and he got really happy to hide behind something and soon became a finger and person chasing fish.
Then I got a 90 breeder tank, and I thought that this time I will have a nice bare tank as he is already being aggressive. Matched all water parameters, totally cycled, waited till night time to keep all the lights down and made it as stress free as possible. Next day he went back to the same behavior of swimming away and being afraid. I tried for a full week to keep him in the bare tank but it was just stressing him out. So I brought the nasty fake tree out of his old house, put it in and in one day he returned to the aggressive nature I liked.
It is important to remember that no matter how aggressive people say Rhoms are there is a lot of scavengering or surprise attacks they do in the wild. You've probably seen this when they eat, the charge at the food and rip it apart. Animals like this need protection and to be able to hide in the wild so they look for it in tanks as well. If you provide it with a hiding spot they will be more stress free, grow faster, and in my opinion become a better pet.
Just my ideas.
