Fish addition urges - opinions please on stock

[Sean626]

What up fellas, I've been recently thinking about adding more fish as its stocked pretty light at the moment but I'm contemplating due to my current fish. Here's a quick background on my tank:

24x24x24 with a 20g sump no refugium

Current stock is:

Midas blenny
Ocellaris clown pair
Yasha goby / pistol shrimp ( never comes out unless its feeding time)
3 striped damsel ( thus the contemplation)

So far everybody gets along, the damsel is still a juvenile and shows no aggression yet except when I added the Midas blenny who was he last addition, he went up to tr blenny to greet him with a few bitc* slaps from his tail but they been fine ever since. A lot of people are telling me that he might get extremely aggressive when he becomes an adult. My gf loves this fish but I'm taking his *** out if I have to. So here are 2 fishes I'm currently interested in getting;

Sixline wrasse (I've heard of a lot of horror stories but their aggression seems to be obvious when overcrowded)
Tailspot blenny ( small fish, compatible with everyone but the damsel and possibly six line wrasse)

So my question to you all is what is the best combo for these 3 fish? Should I remove the damsel? If I were to keep the damsel, would these additions work? Thanks all

 

[cymaster007]

Skip the six line and get a nice fairy wrasse.
The 2 blenny's midas and tailspot will most likely fight also.

 

[Lexusman25]

I have a six line and he has been a model citizen so far. He's not aggressive but I have a big chromis that thinks he runs the tank and when he goes after the sixline, the sixline will put him in his place!

 

[Sean626]

I thought blennys were compatible? I can see why thy fight if there isn't enough holes or rocks for perching but my tank has several