So for an actual wrasse selection you have to consider the other fish. If you stick with smaller, less aggressive fish then I suggest smaller, more peaceful wrasse and naturally if you are planning more large boisterous fish then you want similar wrasse. With wrasse never get two of the same species but rather a variety of species.
I'll just do the peaceful for now. I will give a quick overview and my suggestions/favorites:
Leopard wrasse (Macropharyngodon): Leopards are generally very peaceful and very pretty (at least as females). The issue is they are sensitive and often struggle with shipping.
I suggest 2-3 of these.
- M meleagris - white leopard: My favorite and on the easier side
- M bipartitus - blue star leopard
- M negrosensis - black leopard: Also very very pretty
- M choati - orange leopard: most difficult of them all sadly
Tamarin wrasse (Anampses): Tamarins are like leopards but bigger and unfortunately more sensitive. These will look impressive in your tank without being at all aggressive. They are also very very pretty!
I suggest 1-2 of these.
- A neoguinaicus - china wrasse: easier then most but still difficult
- A meleagrides - yellowtail tamarin: same as above
- A twistii - yellow breasted wrasse: Same as above
- A lennardi - Lennardi's wrasse: very difficult but very very pretty
- A femininus - femininus wrasse: same as the lennardi
Flasher wrasse (Paracheilinus): Now onto something a lot easier! Flashers are flashy and though sometimes shy make great fish.
I suggest 2-5 of these. They are all basically equally pretty and all easy moderate difficulty.
- P cyaneus - blue
- P filamentosus - filamented
- P attenuatus - diamond tail
Fairy wrasse (Cirrhilabrus): These guys range completely in terms of aggression but if you keep from having them too closely related you should be fine. You have a great group already but
I suggest 3-7 of these and will only add:
- C exquisitus - exquisite fairy: A good addition with the 5 already on your list.
Pig wrasse (halichoeres): These are often seen as the pest eaters but there are some very pretty ones. They can be more boisterous though like your melanurus.
I suggest 2-4 of these.
- H iridis - radiant wrasse
- H chrysus - yellow
- H marginatus - dusky
- H melasmapomus - earmuff
Lined wrasse (Pseudocheilinus): Little monsters but for some reason very popular. This is where your mystery wrasse belongs. The sixline is the most popular in this group.
I suggest 0 of these.
Cleaner wrasse (Labroides): Only add if you have a lot of fish but a great fish if you can satisfy its need to eat off other fish. I suggest getting a captive bred one from biota or waiting till you have a lot of fish.
I suggest 1 of these.
- L dimidiatus - blue streak cleaner