I agree with virtually all of that from the OP.
Plenty of people want a "name" or established Championship manager bit, to me, we've been there done that and whilst you can get short-term gains (Mackay/Warnock) it doesn't actually progress the club.
I didn't rate Harris as a first team manager but he was the first manager that paid any attention to the Academy for years. I don't think Harris had the ability to manage at first team level but creating that pathway into the first team could stand us in good stead for the future.
I would love a new, young manager to come in and take a more holistic approach to the club which would enable us to get a bit closer to that self-sustaining model that most clubs aspire to.
It would split the fan base because I know, understandably, many fans want us to play safe with an established manager but I think any appointment will split the fan base for many reasons (with the possible, unlikely, exception of Wilder).
It's a very interesting appointment that's for sure.
Finally, I share your doubts over Dalman's and others comments about Tan interfering with tactics/selection, etc. He may well tell a manager he'd like us to play more directly, etc., but that's a million miles away from selection. On the other hand, if he has been selecting the team/tactics then with two promotions to the Premier League on his CV he's the most tactically aware owner in Britain