Purchasing my first coral

Hey all, I need a little help from you. I'm a little nervous about adding my first coral to my nano. It seems really intimidating, and I don't want to mess it up. All the problems I've seen on here have really gotten to my head. I think I've done pretty well on my first tank so far (0 deaths!), but for some reason the coral thing is a whole other animal in my brain. There are so many options and factors involved, that I need some advice from all of you as to where to begin.

I have a 9-gallon nano that's about 7 weeks old. First, I know age doesn't say a lot for a new tank by a newbie, so here are my current parameters:

pH: 8.3
Temp: 78
Salinity: 1.025
Ammonia: 0
Nitrites: 0
Nitrates: <5
Phosphates: 0.2-0.25
Calcium: 420
Light: 1200 lumens @ 6000k (stock LED)
Tank: http://ift.tt/1paXx76

I'm wondering if I'm in a spot to begin introducing coral. I have a pod of zoas and a pod of palys, which are doing very well, but I know neither of these are good gauges of my true water condition, since they are hardy as hell.

If I AM okay to start introducing, what would you all recommend for my smaller tank? I don't think I'll get many...maybe 2-3 total. Chi told me I was already overstocked in terms of fish, but I'm wondering if that would also apply to corals.

Livestock, just in case:

5 blue-leg hermits
5 Astrea snails
Peppermint Shrimp
Flame Scallop
Lawnmower Blenny
Oce Clown
Pom Pom Crab
Feather Duster