I'd say De Gea, Rafael, Carrick, Kagawa, Januzaj, Mata, Fellaini, Rooney, RvP and Welbeck are top 4 material.
Some of the names left out that list may be bemusing but at the moment I don't class Jones/Smalling/Evans as top top players. They most likely will be or can be on their day but their still developing especially in the case of Jones/Smalling while Evans can be inconsistent and I couldn't imagine him being a starter for the other top 4 teams.
Also I feel if Fellaini was playing for Chelsea instead of Matic or for Arsenal he would of stood out as good top 4 player, he is struggling in our system at the minute and with our poor form. This season is a write of for him but next season is when we can judge him and I feel he will show his worth. Even Mata has struggled at us so far and there's no doubting his ability.
De Gea is the best keeper in the Premiership for me, and Rooney & RvP are in the top 5 strikers. Welbeck is not far behind Sturridge who is banging in the goals for Liverpool, he's a number 9 who will never really get a true run of games there.
Although I believe our two CM's are good players, they are not compatible together. We need a creative midfielder and a box-to-box midfielder. Fellaini and Carrick in a two man midfield would never work therefore lies our problems in terms of creativity. Also they struggle due to the system we play and the poor form of our wingers.
Our defence is another massive problem. There is no dominant figure in the back, most strikers would fancy their chances against any pairing of our CBs which would of never happened a few years, also the same with most wingers v Evra these days. Even during Fergie's last year, we were leaking goals far too easily.