To be honest, if you wanted that many fish, you would need a much larger tank then 55 gallons. Somewhere in the neighborhood of 75 - 100 gallons and above.
The scooter blenny and the sixline will almost definitely compete eachother for pods
, and the sixline will most likely win considering its aggressiveness coupled with the fact that scooter blennies are pretty slow and sluggish fish.
The hawkfish might also get pretty territorial and could cause problems further down the road. Not sure if you plan on having a reef as well, but the angel may or may not nip at coral, it's very hit or miss with them as coral is part of their diet in the wild. Also, the hawkfish is the same way and should be added to reef tanks with caution.