I am confused which payment methods to offer to my fellow players to have them pay for the vip rank.
Could you name me what you use and why?
I only offer Paypal by now but not everybody has this.

Some players, especially the younger ones I believe could use some of these: Mobile call payment, Mobile SMS payment, paysafecards..

Also Credit/Debit cards and Skrill.

Stripe & Paypal covers the most popular methods, you could also do crypto, but that's not as popular.
Try using tebex, they offer many gateways !