I've never been the largest fan of the rami movies. I don't hate them, but they don't gel with me. The first is kind of obvious: it works, but it's mostly material any fan knows like the back of their hand. When one half the movie is re-telling one of the most prolific super hero origins, and the other half is a Green Goblin re-tread, there just wasn't much to go wow over the way the fight in the Avengers did. 3, you explain well, everything in it (with one exception I;ll get into) is well done and worked on it's own, but you can't but fried chicken, mountain dew and chocolate ice cream in a blender and come out with the ultimate drink as great tastes don't always blend. 2 had the same problem on the other end, Peter's life got so sad sack it was hard to take seriously, especially when so many problems were self inflicted less by Spider-Man and more by shitty time management and pre-prepared excuses. Spider-Man is supposed to interfere with his life, but it did to such a extreme it was hard to see how he could manage being a hero when he couldn't master early life.
That lack of subtlety is the big issue with 3: aka dark Peter. Yeah, what you say is the point, but these kind of stories only work when the change is gradual and natural. When you don't know if there's a problem at first until something goes wrong. Dark Peter was more in the vein of those old drug PSAs that had someone go from one reefer to selling their body for heroin almost overnight. So instead of Peter trying to be cool and badass and finding it comes witha cost he's not willing to pay, we get "just say no to alien symbiotes".
I'll also disagree with venom as a bad character, at least in concept. It wasn't that Venom was just "evil Spider man" but rather it was totally fucking personal. With most of his usual bad guys, they wanted money or the like, and they didn't usualy kill for shits and giggles or weren't likely to be stopped by the hundreds of other heroes in the city. Venom lived to destroy Peter, and had the power set to do just that. That single mindedness and power set makes the ultimate nemesis. The problem really came from the comics code at the time and the usual comic book rules: Peter had very little life for Venom to destroy, and what little he had, he couldn't touch because you couldn't kill supporting cast willy nilly. Then, he quickly got overused, and it went downhill, bounced back a bit with the Lethal Protector concept, but lost that and fell apart completely about the start of the clone saga and never bounce back totally.
And on a personal level, could you please read your own pice on adhering to the source material and then elaborate on why a less nerdy Peter or the thing with his father is a problem beyond them being a change from the source material. I'm no defender of the new movies or these decisions, but there are times I get the impression you give other people crap for fanboyism and dislike of change you can partake in yourself.