automatically available nickname suggestion

[Mezo]

You may not understand what i mean ,

there are alot of new users when they try to register , system tell them username or email is taken

So our system should give them automaticly choices for availabe nicknames

or

we must disable nickname usage , and in regstration process it's enough to register with only email ID , and we can change nickname to be like First name + Last name

so email will be the only way to login if our request can't be done

Regards