First, IMHO, at the start of the account, often players end up putting in atrocious IGNs after getting frustrated by repeated rejections of their favorite play-names. I’ve seen random text like “asdfasdf”, “anon1111111111111”, etc. Seeing how casual/ flippant the play-name appears, I don’t think any serious alliance would want them in their ranks. Perhaps, FG could enable play-name change at a stiff cost of 500 Gems (after 1 free re-baptism), so players think carefully before they (re)name their accounts.
Also, given that multiple accounts for one player are discouraged, the propensity to open sequential accounts like “AriesRising01”, “AriesRising02”, etc. could be prevented by restricting the play-names to letters only, instead of alphanumeric. Besides, this will prevent play-names with sensitive info such as date/ year of birth, which are often banking related (i.e., TPINs, ATM PINs).