Do you create alts on another acc or same acc?

As far as i know , the benefits of creating a addional character on another account is better than on the same account because you get to recieve the monthly event rewards which is only given to 1 character on 1 account and the event day 1,2,3.. is not shared among the characters in the same account so this is pretty good for your alts or secondary character. While on the other hand , characters on the same account may get special rewards for example previous event that give you 100% temepering stone and other events that give you some small items from reaching to lv 25/35 on the same account.

So i just wanted do you guys create alts on the same account or on another account?