I wouldn't be surprised if WWE set the wheels in motion to break up The Shield sometime this year. Fact of the matter is, The Shield has peaked. They've gone about as far as they're going to go as a team by holding the vast majority of mid card titles in WWE. And I don't think any tweaks would help achieve a goal of sustaining longevity and achieving more success. Adding Punk didn't help The Nexus, it made things worse. The Corre was a poor man's version of Nexus, and the stable never picked up any momentum. With The Shield, I think it's best to cash out while they still have some value left, because it won't work out well if WWE pushes them pass their expiration date. You have to face facts, The Shield's shock value has faded away a lot, and they're just kind of there now.
And yeah, it's obvious WWE is grooming The Wyatts to take over as the top stable in WWE. The Shield, they were a breath a fresh air and something different. The Wyatts are something different and refreshing, and with more time to come into their own, they'll take the top spot of being the #1 heel stable in WWE. Variety is essential in pro wrestling, and you can't get anymore unique and eccentric than The Wyatt Family.
Of course it shouldn't happen now, but I could picture a scenario, where Harper and Rowan take the straps of off Rollins and Reigns. I don't know what you would do with Bray, because the US Title would be an odd fit for his character, but Bray could be the mouthpiece for Rowan and Harper as champs, as they tear through the competition.