I voted 'disliked it now like it' - I think, I've just read three pages of comments so I'm not 100% on what I voted about half an hour ago. But 'disliked it now meh' would have been a better fit. I have a grudging respect for season 4. I've rewritten all the seasons of Angel so that Doyle lives throughout and rewriting them has given me a whole new perspective on the show and how each season fits together and, looking back on the whole experience, I remember season 4 as one of the easiest to rewrite - so I have to give it points for that.
Season 1 is pretty much entirely motw episodes, yes Wolfram and Hart is in the background, but their wacky schemes are different every episode - there isn't really a story line beyond 'set up'. But it is fun in its simplicity (with a few howlers).
Season 2 has a compelling story line ... but not enough story line to keep gong an entire season. The beige phase - whilst presumably masquerading as story arc because Angel is separated from the group - actually includes some of the weakest motw episodes there are. The story arc finishes completely in episode 16 and then it has two motw eps and the Pylea arc. There's actually only 7 story arc episodes in the whole season, what we get is very intense - but over 22 episodes also really sparse.
Season 3 is split into 3 really distinct phases: motws before Darla shows up, pre kidnap and post kidnap. The motw are good enough, but they are what they are and then post kidnap is just a bit ... boring. Add in the motws inside the two distinct story arc phases and - there's not a whole lot of good meat in there. A lot of the padding is really good, but that is dragged down by some of the story arc being not that compelling. There's an over reliance on love triangles to create added drama. And then Cordelia ascends to a higher plane of existence and the less said on that, the better.
Season 5 was the season that surprised me the most in the rewrites as having the least story to get your teeth into. It's a season of great one off episodes but again there isn't much of a throughline beyond 'we work for Wolfram and Hart now'. In a way it was very like season one but without the simplicity and freshness. s5 is the series my opinion changed on for the worse once I'd really studied it (although burn out may have been a factor by that point).
But season 4 ... season 4 is all story line (and I say that as a good thing despite enjoying stand alone episodes as a general rule). It has a place it is going and it is getting there, it has something it wants to say and it's going to say it. I don't think they knew exactly what they were doing all the way through, and some of the twists are convoluted and even down right silly, but at the end they do have a cohesive whole that makes a sort of sense. They keep raising the stakes and even though the last few episodes are completely different in tone and feel to the rest of the season (as also happens in s2) they are still linked to what came before (unlike in s2) and that contrast in tone is purposeful. Season 4 has scale and ambition that none of the other seasons of Angel can match and I admire that about it. I found it much easier and far more enjoyable to rewrite s4 than I did s5.
But my respect is only grudging, because whilst I appreciate the scale of the story ... I don't actually like the story. I don't mind the idea of Jasmine and the ideas they explore about free will and I am willing to accept without too much question that everything that comes before is what is necessary to bring her into the world. Fine. Why not? But I don't like the love triangles, I hate everything about Cordelia - her cheesy bits up on the higher planes, her amnesia and then her possession and her dressing like a pregnant dominatrix. I do feel for Connor, I am a Connor apologist, but he is a sucking black hole on the screen (which is nothing against Vincent Kartheiser - I love Connor's Mandy/ Jasmine duet with Angel and I really like him in s5). I'm not as icked out by Connor and Cordy as most people - but I am icked out by the cheesy ass terrible dialogue she uses to seduce him: 'Your whole life you've never had anything real, I just want you to have something real.' Oh just bang him already. I am icked out by Cordelia and the beast though - and I don't like her cheesy villain lines. Angelus is a bit of a let down - such a pale shadow of what he was in Buffy s2, Faith is supposed to be dying but then somehow just survives and is fine, and then it turns out Skip is evil and he retcons the entire show to have all been part of this insanely convoluted plot all along.
So yeah - for me season 4 succeeds as being an epic tale, it just doesn't succeed as being a particularly good or well written epic tale. I don't feel any particular need to sit down and watch all 22 hours of it ever again - and because it is so serialised there aren't really any episodes I would pull from s4 and watch as a one off out of order - which s2 and s5 are full of.