It is just too much indeed. Just charge 99 cents for one week for a old game and 1,99 for a new AAA one. That is fair.
1,99 for one month of a old one and 2,99 for a month of a AAA big title.
More than that and I am out.
By the way, PSone should be 10-30 cents for one week and a PS2 title should be 40-50 cents.