Make both, switch off between them when you get bored. You will want a main for money, and a pure for when the new pking update comes out. You could probably play on both at the same time, afk train on pure and do stuff on main, or vice-versa.
If you are making a new one, why would you make it a "main"?
Start off by making it a level 3 skiller. Get a lot of skills up to where you can make good money.
Then make it a pure, I suggest a hybrid pure. After you have fun with this for a while, go ahead and get 45 defense for a rune/serker pure. Then have fun with this.
After this I would say get whatever defense level you want and then you're set with a pretty kickass account.