None of us know him personally, but the court case he choose to have televised gave us a good glimpse.
I'm not just talking about his Amber era, but in general.
I think he's always been snooty and pervy. The lovey dovey stuff he did publicly with his early loves were cringeworthy (the non-stop "we're so in love" campaign with barely legal Winona, and that sexual photoshoot with Kate Moss) I can't stand his purple prose way of talking. He always tries to appear so cool and above it, and spoke non-stop about how acting isn't a real job and he's just doing it for money; he complained about fame, even though he clearly loves it.
He's a hypocrite. He spoke about how France is the better option to raise his kids because they were too good to be raised in USA--a land with drug dealers on every corner. Depp had no problem drinking and drugging around his kids.
As for his looks: I think he's overrated. He's very good looking certain roles like Blow and Chocolate, even the Pirates franchise--he looks better with long hair and facial hair. However, I never found him attractive with his normal, clean-shaven appearance with short hair (like Donnie Brasco, Nick of Time, Rum Diaries) He looks best with eyeliner.
Acting ability? It depends on the character. He's good at the over the top type, and yes, Jack Sparrow is very charismatic But he's bland and replaceable in more normal roles.
Also, the legal mess with Amber Heard showed just how vindictive and relentless he is. I don't know or care if she abused him, but Depp clearly abused her too. Go to the subreddit DeppDelusion and you'll see all the stuff he's done. Forget about the physical abuse for a second, and look at the emotional abuse. There are texts and phone call recordings where he's calling Amber old and over the hill because she was approaching 30, making fun of her for not having kids by 30, accusing her of being a gold digger but getting upset when she tries to work.
Unless he has severe memory loss, he must know that he was abusive. The fact that he'd seek a televised trial to show off what a good guy he is, shows just how arrogant, delusional and mean-spirited he is. He clearly has a scat fetish, so if Amber did shit his bed, I assumed Depp liked it. He's also suing a different guy who claims Depp stole his lyrics--these lyrics were published years before Depp released his recent album. How can he think he can get away with this? He's a rich bully who knows he can silence poorer people with lawsuits.