Re Sissoko it's worth mentioning that he only really emerged as a "leader" when it became apparent that Aurier and Ndombele basically needed a babysitter and he took on the role of an older brother to them.
We wouldn't need leaders like that if we stopped signing clowns.
Erm….
Whilst I agree with you sentiment to a degree, and I'm all for signing better players, I think it's more accurate to say that Sissoko became a leader when Dembele's absence became a crippling factor at the beginning of the squads decline. In a squad stripped of a backbone, Sissoko becomes the 'goat'.
I disagree that we wouldn't need leaders like that. We've
always needed leaders like that.
Sissoko was like a gaffa tape lesser alternative temporary fix for losing Wanyama
and Dembele who were both firm in midfield. Before that it was Scott Parker partnering Modric, before that it was Palacios partnering Huddlestone. When these players came into our squad they always made a positive impact and added rigidity to a, too often, too soft centre. (Redknapp having to field a midfield pivot of Modric and Kranjcar in an inevitable heavy loss comes to mind.)
Look at how Dembele was willing to fight in the battle of the bridge.
Who, apart from, Sissoko, has had any kind of physical stature like that on he pitch to let the opposition know not to f&*( with our players?
Winks? Skipp?

Even Hojbjerg, "the viking", is lightweight and passive in comparison to prime Dembele, and he annoys me sometimes with his seeming passivity in key moments. Anyhow, I digress.