I don't think that as a Sprint subscriber our options are all that limiting (unless you are still locked in contract). Buying a phone off contract opens you up to several options.
1. T-Mobile offers great pricing plans if you bring your phone (depending on your coverage reception and data may even be better) and you are not locked in a 2yr agreement.
2. A pay as you go, such as straight talk, might also be a good option if you don't consume much data.
I notice that I constantly have my phone running wifi off of my office and home wireless and my data consumption on my bill looks relatively low.
I'm not saying that this is for everyone, but I've been on several SERO forums where former sprint users dumped sprint and wound up with better service and saving money in the long run.
I've been with Sprint since 2003 and for the longest time I thought that Sprint was it but over time more options have become available so, my point being, the market has changed and I think that there has been a shift in the mobile service industry to where it is more of a consumers market.