I still worry about buying from this age group. Thiago Alacantara was 29 when he joined Liverpool. Absolute class act who Klopp felt would change the dynamic in their midfield. Was earning over £200k per week. Look how that 4-year contract went.
Then you have similar players like the Silva's, Bernardo and David, and players like Bruno Fernandez who operate or operated really well at 30. I guess we find out what they're like at 31 and 32 or whether they get overrun like Eriksen. He joined Utd at 29 and is now 32. He's never looked like he can hold his own in the physical battle in the PL midfield in a Utd shirt as his legs go. He should have gone to Spain.
I still think that buying players like Ruiz carries a very high risk.
For me, Joao Gomez is a player worth looking at for Spurs. Proven in the PL, needs that step up and is only 23.