With Gronk, Allen, Lengel, Williams and Housler, the Pats appear to have a decent core TE group already. OTOH, there are obvious health question with both Gronk and Williams and even with Allen, to some degree. And, IMHO, Housler was picked up merely as a backstop in case the Allen deal didn't go through. Until he demonstrates otherwise, I see Housler as mostly Camp fodder and would rank him below Lengel on the depth chart.
Butt seems a bit like a slightly smaller version of Bennett (a good thing), and a pretty decent fit. A rough survey of current rankings and projections has Butt going in the late-3rd or the 4th, but it's hard to say whether or not that reflects the market having already "priced in" his ACL injury/lack of availability over the summer (at the very least). If not, he could still fall lower. As it stands, BB might have to spend as high as the #96 to select him, but could possibly still snag him at #130.
Anyway, with at least 2-3 decent guys at TE under contract, it could allow BB to take a mid-round flyer on a TE with high potential, but who might not be available until the second half of his rookie season (if at all).
OTOH, given the potential health issues with the TEs under contract, and given BB's experience with promising TEs who are already working through a significant injury, and given that there are other TEs in this class who may have equal potential/fit who are healthy, I'm guessing that BB would be unlikely to select Butt before the fifth round.