I don't really ever pay full price for games anymore. $60 for a game is a lot of money, so unless it's a game that I absolutely have to have right away, which is literally never anymore, then I'm fine with waiting months or even years for prices to drop.
Console games are just ridiculously expensive. Even after several years, the lowest the prices get is usually around $20-30. That's why I've been playing more games on PC the last few years. Games go on sale pretty often and I usually get the games I want for $10-15, or sometimes even less than $5.
Anyway, to answer the question about price vs play time, if I get about two hours out of every dollar I spend, then I feel like I'm getting a pretty good value.