Choosing a name that isn't taken has always been a world of pain for me. I don't want to be forced to pick something ridiculous like xX-L0n3R-Xx, or something out-of-place like Loner1989, or something from a generic nickname generator or just the same thing but written in latin. My nickname is "Loner", I want to be just "Loner".
If it's simple and unoriginal and there's already a thousand other Loners running around - let it be my problem. There's no need for you, developers, to solve it. It creates unnecessary work for both devs and the players. And if I later want to change my nickname to something else - I want to have that option too. Account systems always restrict you in that respect, and I'm sooo sick of it.
Not saying account system shouldn't be there. In fact, I liked how it worked in Soldat Portal - your ID was just a short string of numbers and letters, but your nickname could be changed infinite number of times and premium users could protect their nicknames from being used by other players. I think that's a fair and convenient way of doing things.
And as yayfrog (and many others before him) said: account system should be optional. Don't want your unique and fancy nickname to be used by other people? Want bonus features like friends list and stuff? Create an account, register Soldat and enable nickname protection. Don't want all that junk? Just pick a name and play (as long as it's not a protected nickname).
