I think that we have some good players in midfield, I'm just not sure that many are fitted to the deep lying playmaker and disruptor roles that Mourinho seems to want in central midfield. Winks and Dier fit this well but beyond this you are making compromises.
A long post incoming, but I think it would be instructive to think about what Mourinho's preferred deep midfield pairings have actually been in his best sides, historically.
At Chelsea in 04/05, 05/06 and 06/07, he hadn't developed a 4-2-3-1 yet - his focus was on his 4-3-3, which usually destroyed opponents that played a flat 4-4-2 (i.e, everyone in the Premier League, with precious few exceptions). But, in general, the two midfielders tasked with 'sitting' and 'shuttling' were Makelele and (in general) Essien or Ballack. The key to remember here, and going forward, is that neither of those two were 'pure' disruptors or destroyers - they had to be able to play as well, and did. Indeed, Makelele spoke often about how he felt the 'water carrier' role he defined was actually inaccurate when it came to him, because Mourinho often relied on him to break the lines with his passing ability.
At Inter, with a classic 4-2-3-1, he played Motta and Cambiasso - they fit your description of 'disruptor' and 'deep-lying playmaker' to a tee (as do the pairing that would follow at Madrid), but again, both could play very well, and either could break the lines with ease, even if one was more physical and the other, more positional. Both moved up into attack at times, while the other sat.
At Madrid, he reached the pinnacle of this organizational set-up at the base of midfield, with Khedira and Alonso - Khedira was the more 'physical' player, but he would actually maraud upfield all the way to the opponent's six-yard box to press high up, while Alonso would sit deep and ping the ball around.
Finally, at Chelsea in 14/15, Matic and Fabregas/Ramires was a bit new compared to all of the others - In Matic, they had a deep sitter who was almost exclusively devoted to screening the defence, and in Fabregas, a wispy, weak playmaker who was almost exclusively dedicated to playing the ball forward.
I think the point here is, a 'pure' disruptor and a 'pure' playmaker have been very ,very new additions to Mourinho's general approach. At his peak, he didn't want 'pure' players - he wanted multifunctional 'do it all' players. With strengths, yes - Xabi passed, Khedira pressed. But their positional discipline varied wildly, they could both pass, dribble, tackle and press, and the only consistency seems to be that one player was more 'energetic', and the other more 'sedate'.
Here, I don't think Mourinho actually would want a midfield of Dier and Winks. Dier is almost exclusively mono-functional - he screens the defense. He can't carry the ball, can't turn, can't run, can't even press up the field all the effectively because of his limited mobility post-injuries. Winks, while he can pass well, is defensively unsound - we look weaker with him in the team, because he can't screen the defense. And he isn't particularly offensively gifted either - he excels at recycling possession, but that's a limited skillset.
Dier and Winks are sort of discount versions of Matic and Fabregas. But I don't actually think Mourinho wants those players.