He's done a pretty decent job at Ajax, no? His achievements look impressive and they are easy on the eye. Won the double in 2018/19 and got them to the Champions League semis for the first time since 1995. They were really unlucky not to reach the final, too. Only 3 goals shy of matching the all-time goal scoring league record set in 1966/67 of 122. Whenever I've watched them in Europe they've tended to play attacking, entertaining football. Maybe he's at his level, who knows. He's certainly impressed at Ajax, though. Seems a bit strange to argue the opposite? Although it makes a bit more sense if you're a Feyenoord supporter..?
Decent? Yes, but their good CL run was primarily down to class players like Donny, F. De Jong, De Ligt and Ziyech. They did not make it to the knock out stages this year after they sold those players.
Their style of football is exciting and attractive if you have those aforementioned quality players. If you do not, you'll either lose a lot of games naively (see Peter Bosz at Leverkusen) or it becomes dull possession based (F. De Boer, LVG with us) depending on where the quality is lacking.
Domestic achievements with Ajax aren't too impressive nowadays considering their budget and quality academy. The gap between them and others has increased through big transfers (great academy and scouting) and CL money. I don't think there was ever a time in the Eredivisie when one team was as dominant (financially) as they are now. Generally speaking, in Holland the manager isn't as involved with scouting/transfers/academy and Ten Hag certainly hasn't been in charge long enough to affect those areas.
Personally I do rate Ten Hag somewhat, but not enough to want him before he replicates his success' elsewhere. He's good tactically, always has a solid game plan and the way Ajax pressures opponents reminds me of Klopp.
For me when I'm looking to rate a manager, I look at the results relative to how I rate the players.
Let me put it this way: I have more faith in Letsch winning the league over at Ajax than I have in Ten Hag getting to a cup final with Vitesse.
The Feyenoord tag is there for a reason. Just do know that I watch quite a bit of Ajax and am always rooting for them in international competitions. (up to this year's final vs us, that is
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I think we missed the boat on Tuchel. Letsch is someone to to keep on eye on for the future. Nagelsmann would be the only exciting appointment for me. Having said that I'm still hoping Ole makes top 4 and gets another year.