Upgrade Sprint HTC Touch Pro2

[ilovecheese]

Have Sprint HTC TP2 here in USA. Installed Sharky Rom. Nice, but I want a faster phone. I have been led to believe (from Sprint) that any future phone upgrades will require a new plan. This seems odd. I started with a Mogul, bought a TP2 unlocked from Ebay and did the swap just by entering the new phone info online. Is there a newer, faster, smart phone I can upgrade to without changing plans with sprint? I have a pretty sweet plan now $29 for 200 minutes and $10 unlimited data. There doesn't seem to be anything close to this plan available today.