And most of those you mention are shown and included in the piece.
The real truth is there are way too many factors that influence improvements, for me at least none more so than the manager. And even here the data will show that there's no such thing as a "new manager bounce" (at least over a 6 month period, as opposed to a two or 5 game period).
The one thing that I "feel" with Spurs right now is that our hires (the majority under Paratici) have improved the squad in every window and that the team has largely been built with an eye on the future rather than the here and now. In conjunction, there is no denying that we have a new manager who has transformed how we play and despite one of the worst injury-hit seasons, I think I've ever known (for comparison look at how Newcastle, Utd., and now Villa have performed with similar but arguably not as significant injury lists). The Bentancur/Kulu is a good point but ONLY if you look in the 6 months period after they were signed, did we improve the following year that led to Conte getting sacked? No, we were worse, went backwards. The point here is at what point do you assess the impact of a new signing, 1st 6 months, 12 months, 18 months etc.....???
I'm as confident about our ability as a club (as a whole - The structure of DoF and technical role, reports of us still using Paratici, Ange and his team, and the academy) since the peak Poch years. On the whole, I like our recruitment, judging that solely on the players we've brought in and even by those that haven't quite worked out yet and ones we didn't bring in as I feel the profile of these players has been by and large wholly spot on, demonstrating also a more joined-up strategic thinking.