Amazon swords would be one of the plants we would recommend with angelfish. They tolerate warmer waters better than most other plants. You might also consider some Anubias which look great on driftwood. If you are wanting to keep 8 Angelfish you would need a minimum 80+ gallon tank. rule of thumb is 1 angelfish per 10 gallons of water. Angelfish will pair off when they hit sexual maturity. As long as your tank is large enough it should not cause any problems. the pairs will defend their territory before and during spawning.
I have read the 10 gallons per fish, I just wasn't sure if that was okay after they've matured. I have a 37 gallon with 5 smaller angelfish (2 black marble, 2 silver, one white) and a 6 inch hifin (this is a temporary home) I have two smaller angels one koi and one tiger altum <=[[is that going to be a problem?]] in my 55 gallon. I am trying to get them to the others size before I get a bigger tank to put all of them together happily. I have a 180 as well, I am just new to angelfish and planted tanks. Also would a 65 gallon be alright? 
180 Gallon River Monsters Tank-Florida gar eating 
37 Gallon Angel Community Tank-2 Black Marble, 2 Silver, 1 white, hifin spotted pleco
180 Gallon River Monsters Tank-Oscar "the Don"
180 Gallon River Monsters Tank-RTC, common pleco, florida gar, oscar 
55 Gallon Pleco Tank-Albino bristle nose pleco, bristle nose pleco, bulldog pleco, clown pleco, BGK , moorii, tiger altum, koi angelfish
