Honestly, what I don't get about the general negative reaction to the show is how little, technically atleast, it does wrong.
Due to the premise, we have settings and missions that actually vary. We've been in New York, the Amazon Jungle, Paris (I think? Some European city), Hong Kong. The missions vary from straight up assault, to espionage and infiltration, to medical drama, depending on what kind of threat they are dealing with. Frankly, we get a fair amount of variety episode to episode.
Characters-wise, we get a fairly diverse group. I won't argue that they didn't start out as archtypes, but so what? Plenty of characters do, but through development, they grow into more. And I would definitely argue that all the main characters are getting development. Skye is becoming disillusioned from her previous view of shield as this oppressive gov. agency and the danger of her philosophy of entirely free information. Her priorites, as we have seen in the latest episode, are being reorganized. Ward is slowly becoming more and more comfortable with working with his team. FitzSimmons started out as nothing but quirky nerds with the only difference being is that Fitz was somewhat neurotic and Simmons ditzy. But Fitz is developing into an intellectual badass and Simmons is getting a stronger handle on reality by being forced to deal with real, personal situations like when she had to face her death. And Coulson has had increasing self doubts about his death and now is beginning to question shield. May is the only one who has remained somewhat static, but I doubt that will last. The characters are gaining depth at a steady pace.
In terms of pacing, there is clearly an overarching story at play here, but they are taking their time setting up the main cast (and status quo) before they bring in the big villains, which is fine by me. Atleast 3 of the 6 episodes thus far dealt with villains who are obviously going to show up again, which seems perfectly reasonable to counter balance that with isolated episodes that focus on the cast. On a minute to minute basis, the pacing seems decent enough. I can't think of many scenes where I felt that my time was being wasted. Which is not to say it's perfect, but if I were to count the time I felt a scene could be cut or shortened, the total would not add up to more than a few minutes at most.
Acting wise, I'm going to keep this short, since I apparently don't have a good eye as to waht is 'good' or 'bad' acting, but the actions of all the characters makes sense within the universe they are in. Yeah, they're oddballs and somewhat cartoonish, but, fuck, if that's your complaint, have you ever seen a marvel movie before?
I'm sure you guys have your own personal issues with them and of course you're entitled to that...but honestly, have you seen walking dead? Or the last 4 seasons of Dexter? Or RWBY (which I actually liked but will easily admit to it's numerous flaws)? Those have truly bad writing. They meander around with pointless characters and plots and incomprehensible arcs and such poor acting that even I can tell its bad and stupidity, oh god, the stupdity. As far as I know, those haven't shown up much, if at all, in AoS.
Agents of Shield is doing a lot of things right. It doesn't mean you have to like it, but just in terms of the mechanics of what is commonly understood to be good writing, there aren't a lot of criticisms I'm seeing being made besides the general feeling of not liking a character because she's 'annoying' or the danger not 'feeling' real, which are more personal issues rather than errors in writing.