Do I have overkill on the lights?
Nope. Sounds like a good lighting setup for a reef as far as lighting.
I have SPS
in my tanks and only have PC
lighting. Of course the coloration and growth rates will be different than under MH
lighting. You also might be limited to the top of the tank as far as placement.
Yellow tang is bad idea for a tank as small as the 29. The tang will easily get 5" in size as far as its body and tangs in general are strong swimmers that like high current and plenty of swimming room. The mandarin reguretfully unless its can be trained to eat prepaired food is also a very bad idea. Your new tank will not be able to support its natural feeding needs. Having them for 9 months is good and as long as your mandrain is eating what your offering it and has good body mass to it then it might be ok. The tang will outgrow the 29 easily though.
With the existing tommato clown and blenny I would suggest a pair of firefish, or a pair of gobies, maybe a dwarf clown like a lemon peel. The lemon peel would give you your yellow back if you remove the tang. I love flame angels but they can have some surviability issues depending on where and how they where collected.