Nothing strikes me as serious now, but down the road I believe things will be. Please accept my comments as constructive suggestions for preventing catastrophe, not as derogatory.
Tiger barbs, should never be combined with some of the other fish, and must be in groups. While they may be "friendly" now, that could be due to their stress at being moved and in a new setup. Once they settle, their truer nature may exhibit itself, and even if they don't actually attack others, their presence is recognized as that of a "bully" by the tetras and others, and that means stress for them. I would see if the local fish store will take them, either outright or in exchange/credit. It would be better for them and the others.
The loaches are social fish that should be in groups, minimum three. Botia kubotai, I assume this is the polkadot loach, is highly social, perhaps moreso than any other loach species. I have three of these, and I have never seen such interaction among fish, all day long. They need to be in groups, but as they attain 5 inches, that is a concern in a 55g; my three are in a 70g and will be the only loaches (except for my quintet of dwarf loaches).
Botia almorhae, the yo-yo, is similar, but attains 6 inches. Must be in a group; they have a social structure so some "aggression" is normal, but not a problem. But with the kubotai, I would not have both species in a 55g.
There are a lot of pleco-type fish, but one would worry me, the gold spot that can reach 12 inches. In my view, he should be re-homed.
The rainbows are shoaling fish that should be in a group of five minimum. They attain 3 to 3.5 inches, and have water parameter preferences a bit higher (alkaline) than the tetras and catfish/loaches.
I do like your tank, with more plants that is going to be very nice indeed. I hope I have been of some help.