the 2 empty weeks will have done nothing for the tank. The cycle will take 4 - 8 weeks to complete usually
The angels are quite small at the moment but they will grow, and grow, and grow and the ywill get far too big for a 20 gal
The plecs if the are common sailfins will get to 18-24" each
The also produce loads of waste
NitrItes need to be at 0 to be safe
NitrAtes have a safe level of <20
the starter bacteria rarely work and even those that do need a source of
ammonia to grow so if you put them in the tank ad did nit feed the tank then they will have died out