I see your MetroPCS and raise you a SIMple Mobile: »simplemobile.com
$50 per month for unlimited everything. Very similar to MetroPCS in the way you get billed. You pay for your phone up front, just like you do with MetroPCS.
I haven't used MetroPCS because I have never lived in their service area. I have used CricKet, which is very similar. I have used Pocket Communications before it was folded into CricKet. Again, very similar...except with Pocket you could get unlimited calling, texting and picture messaging for $25 per month once upon a time. Now that, I contend to you, is a good deal.
So, with that knowledge in mind, take a look at Straight Talk or SIMple Mobile. Both use T-Mobile's network (Straight Talk gives the option of Sprint, AT&T or Verizon as well). Both offer unlimited voice and texting, and unlimited (within reason) data. Both are in the $50 per month range. MetroPCS no longer has a monopoly on cheap unlimited service, and hasn't for a few years now.