What's your ultimate goal? To go to TPS or fly U-2s? If it's to go to TPS and you're a cargo/tanker pilot (assumption made by me based on the fact that the CAF porch won't release folks to the U-2), then you're probably better served continuing in your MWS as that extra experience can help in future applications (assuming you don't get in).
On the other hand, having a varied flying background is usually looked upon favorably upon TPS selection boards, but ultimately, you probably have a better chance of being selected as a heavy pilot than a recce pilot based on recents classes.