Wow...I don't know where you got that list of candidates, but if you put many of those in a community tank with seahorses, I predict starvation for your hippocampus.
The first one that caught my eye is the green chromis - harmless little fish, right? However, green chromis are PIGS when it comes to feeding. They feed at the surface and will devour anything before it gets down to the level where your seahorses are passively waiting for food.
The green Mandarin and seahorse compete for the same foods - that is live copepods. One or the other will suffer unless you have a HUGE tank with lots and lots of flourishing live rock.
Bangaii Cardinalfish are also aggressive feeders.
I have (2) black occellaris clowns, a single small royal gramma and a pair of twin spot gobies in my seahorse tank. I always feed the community first, then turn off the pumps/powerhead in our 29G Bio-Cube which signals the seahorse to come to the front of the tank for their mysis shrimp. The other fish hang to the back of the tank because they have already been fed.
Between the 3 daily target feedings, the horses graze on copepods on the LR.
Just my opinion...