If I was going to have a small flock (which was my intent when I got the first 6  LOL) I would get a mix.  The benefit, you get to know each girl really well, learn about the breeds, get eggs and can always tell your girls apart.
the first 6 I ordered, which are my main layers right now, were:
2 BAs - really wonderful layers, personality and just fun
1 SLW - great layer, a spoiled mess and totally cool to have around
1 EE - another spoiled mess, beyond sweet, good layer (one big green egg every other day)
1 NHR - great layer and nice personality
1 Light Brahma - great layer, sweet, deep voiced growler and just a doll
The next age group for me are 5 BAs and it is very hard to tell them apart.
My youngest group is a variety of 21 and 2 of those are BOs.  One is really sweet and the other very standoffish.  So, who knows.
Good luck with your choice and congrats on entering this crazy chicken world.  It is too late for treatment and the addiction is tons of fun.