Part of my concern with the summer transfer was this, but I think this was intentional (because the right players weren't available, Thiago being the only one, yet we missed out on him, I think even Thiago thought he was coming to United).
Basically, as the deadline loomed, he wanted to dip into the market, he missed out on the right player, so he thought about another area to add to, that could add another dynamic to our game, even if the right player wasn't available, he maybe realised he could start to plan for the years ahead now, so bought Fellaini, and also Mata who we have a similar player in Kagawa.
I think we need a ball-winner which looks to be Carvalho in the summer, and a creative deep lying player to replace carrick, and a box to box but as none of those were really available in europe last year he bought what he could, Mata and Fellaini may look a bit out of place so far, but I think they aren't really in the system he wants with the right players this year.
I do agree to some extent that SAF did leave the squad in a bit of a state (in some areas) like losing Scholes and Pogba not given a chance so he got fed up, then Giggs retiring, Rio and Vidic past their prime, and perhaps some of the younger players haven't developed as much as we would like, (they will given time) the thing is this season is high pressure for the united players and under new management doesn't help, yet that doesn't neglect we should be top 2-3 this season.
I think the board realises, there does need to be a world class midfield, a top winger, and a strong back four, because other teams have strengthened a lot last summer, and will again this summer, the team can't be left behind, the money will be recouped by sponsorship deals, if it doesn't strengthen the money will go elsewhere.