Three schools in the middle is going to look rather cramped, even in a 36 inch tank. And six is the minimum for those tetra. Some people even have nipping problems with just six. I like to do schools of 10 or more tetra, so even if I lose a few to disease or stress I will still have more than the minimum number. Plus, schooling fish look so much more impressive when maintained in large numbers. So let your friend choose two of those schooling fish and increase their numbers and then drop the third school.
You are right that the honey gourami is a good fit for the tank. They are very peaceful and will enjoy the calm company of tetra and rasbora. We also have a profile for them here: Honey Gourami (Trichogaster chuna) TFK Profile