Review of JoJo's Bizarre Adventure: Golden Wind

I have a simple heuristic regarding JoJo - a good part is followed by a bad part. Considering how much I liked Part 4 (my favourite, just above Battle Tendency), I had braced myself, but this one still fell flat. In my review of Part 4, I said how a simple change of genre and deletion of the "save-the-world" trope fixed everything that was wrong with Part 3 for me. That was a very creative solution but also a roundabout way of going around things. In Part 5, Araki is more direct because this is a very simple rehash of Part 3. Now, I thinkthis is genuinely a much better version all things considered but it still isn't good enough for me.
Primarily, I did not like the characters. First, the design just didn't work for me and as the series went on, I could not get invested in any of them which is a shame because quite a few of them actually got full character arcs (a rarity with Araki). Note that the design here is much different from previous JoJo parts, Part 4 seems to be somewhere in between the art style of 1-3 and 5-?. I liked the previous art style better and I'm sad that Araki does not draw the poses with the same flamboyance and frequency anymore (peaked in Part 2). On top of that, the character designs here come across as plain weird to me, I cannot take a stupid-looking character seriously. Can we stop with the open chest thingy please? One of the reasons I'm still looking forward to Part 6 despite vaguely knowing its negative perception is because
a) The mc is a girl so goodbye open chest thingy
b) The character designs overall look much better - much less weird while still being trademark JoJo level wacky
Secondly, the protagonist Gio was the plainest JoJo we've had since Jonathan. It's incredible how he has Dio's blood but that part of him is never explored. Sticking to remnants of previous parts that are left hanging - where did Kouichi go? It's difficult to see how he would have fit into the whole mafia business but then why have him here at all? It just reeks of Araki wanting some connections to previous parts in what is a pretty blatant spin-off. The villain was good, at least the whole multiple-personality business was.
Lastly, the final fight was not good. Final fights have been the high points of the previous parts but here it fell flat for me.