Starting with the angelfish. This is a shoaling species and when kept as a group there needs to be at least five angelfish or some will inevitably get picked on to the point of death if a male is present. This requires a more spacious tank to allow them their hierarchy and territories. A "pair' is possible but only if they have selected each other and bonded; inevitably that will mean spawning, and this could be trouble for the other fish (non-angels) if any are present. So that leaves a solitary angelfish. I am not someone who likes to recommend keeping a species in a situation that is completely unnatural to the fish, but a single angelfish is your only option except for a bonded pair.
Moving to the other fish, this will depend upon the angelfish issue. Tankmates are possible but must be very carefully selected, avoiding any small fish likely to be eaten and any fin nippers; and with sedate long-fin angelfish in the tank, many other otherwise peaceful fish can become fin nippers.
"Big fish" needs to be qualified. The tank space is not all that large, to the fish. If the angelfish is forgotten, you could look at some of the medium gourami, like the beautiful Pearl Gourami; you could have a small group. This fish will grow to 4-5 inches which is a fair size but they are very sedate, not active swimmers, so their need for more space is not an issue like it would be for active fish.
You will need to cycle this tank before adding fish, unless you have live plants that are showing signs of growth. There are articles on cycling in that section of the forum. Cycling can take from 2 to 8 weeks normally (except with plants).
