What I do is generally have a guest viewing side and a maintenance side. Thick forest hide the fence on the maintenance side and some trees in front of towers and between galleries to spread the forest around. Shrubs tool near fences, edge of forests, and edge of ponds but leave most open grassland as the short cut grass in herbivore pens to imitate the grazed field look. For carnivore only pens, after placing as much forest as possible while maintaining enough grassland, shrub tool the whole thing; no herbs to cut the grass.
-I just left for a trip so I can’t show you screenshots till next week, but here’s how I make really cool looking swamp/marsh. Medium to large pen on mostly flat ground and fill with water tool (and try to find one of the lower areas on the map so it makes sense: Nublar map has a spot already set up this way). Fence in the area and place a Gyrosphere; have the path wind around avoiding any straightaways but also not coming too close back to itself or the fence. Use the remove water tool to select sites for feeders then water tool around the edge of this to make it look more natural and less “here’s a perfect circle of land”. Now, shrub tool everything. Next comes an important option; Spino Marsh or Bary Swamp. Spino needs a lot of grassland so place a bit of forest around the feeders and you’re done. For Bary Swamp, cover with forests but then go back and delete most of the dense foliage but still maintain a canopy. Last is what dinos you want to put in it is ultimately up to you but dilophosaurus looks good in here and a big group of them provide a good ambient sound to the environment while the only “swamp” looking dinos they don’t work with are the hadrosaurs. Now just put on some Cajun music, take a ride in the gyro, and if you see a Baryonx or a Suchomimus just call Paw-paw and say “Parrain! Dey got dem a tree-shaker in der!”
-Taking a cue from what we find on Sorna, you can hide feeders from the player by forest canopy and from guests by placing forest thick enough to create thick foliage for an all-natural appearance; but this must be done in a way that a Jeep can still reach the feeder for resupply via a passage through the jungle hidden from guests.
-Generally placing unsightly buildings like the creation lab, power stations, or ranger/acu off to the side surrounded by forests will go a long way to make the whole park more asthetically pleasing. Except on Pena: then go ham on the military prison look.