There was a recent issue with Maestro card suddenly being disabled from GG. This has apparently been quickly resolved now. However, to help avoid anything similar, the more alternative payment methods there are, the better, from everyone's point of view.
Adding Paypal could certainly be useful, though popular as it is, not everyone has a PayPal account.
One of the best payment systems would surely be the option to set up direct debit payments wouldn't it??
*Works with all banks, always.
*No need to possess any kind of cards, Debit or Credit.
*No hassles due to cards being routinely updated with new numbers etc, this then commonly causing failed top up payments. Followed by the hassle of having to change registered card data online etc.
*Totally safe. Many folks are still wary about giving their card details out to anywhere on line.
Seems like a no brainer to me.
PS There is a newly erupted discussion going on about this idea in contribute here (May 2016)........
Also, this idea was originally published in the somewhat superior old 'Ideas' forum. There are some 9 pages of comments and debate over on the disabled Ideas frozen archive here........