Gold barbs are just as active as the danios in my experience. They do get more docile when their numbers increase but they still move around a lot.
At 20 golden barbs, your stocking pretty heavy for the middle region. esp since the rams are territorial and are mid-lower region fish, the large amount of barbs may illicit aggression. The angels are also mid fish. Thats a lot of fish for one region.
Jwest, what are the dimensions of your tank? If its a tall tank, then you can stock ur middle with more fish, but if its standard, i would increase the # of dwarf corys, as they do better with larger numbers and reduce middle region fish like the barbs and danios. However, barbs will get more aggressive the less of them there are, so make sure you keep at least 6 barbs if u get them.
Do you plan to spawn you gouramis? If not, then i dont think u need to worry about them getting disturbed. Also i find it quite difficult to find male pearls since they sell quickly due to their bright red breasts, people tend to pick them first. My lfs always ends up with only females only within a day or so of restocking.
Female pearl gouramis are not as territorial, i kept 2 together and even though there was adaquate space for them to pick their own territories, they swam together a lot. Im sure you can get 3 or 4 more pearls at the top and cut back on middle region fish.