I only read the 1st few pages of replies so my apologies.
1. We need to stop with the ovrarching generalizations based off of personal gameplay experiences. Saying stuff like "no the police aren't tough, you just suck" or "police are easy because I barely get chased when I sideswipe a police car"...statements like that don't mean much because this is the KING of open world games and you get a slew of WIDELY VARRYING RESULTS no matter what you or any other player does. You can do the same things 20 times in a row and you'll get 20 different results most of the time. Sometimes they're a breeze to deal with, sometimes they seem way too hard. It's GTA, and that's the beauty of the game.
2. With that being said, I think one thing we can all agree on is that the AI for the police (and enemies in general) needs to be improved/evolved. It needs to be more than just
player gets star(s) => hordes of cops try to ram/shoot player as best they can
The GTA games have evolved in many ways but the Police AI has remained relatively the same, going all the way back to the 2D GTA games. In fact, one can argue that they have devolved over the years. Back in the days you could get the army to come after you with 6 stars, hell Vice City even featured the undercover police in the sports cars that would come after you once you hit like 4-5 stars (damn I really miss that). On the flip side, in Vice City 1 star would = a couple officers chasing you on foot with night sticks. The different wanted levels actually MEANT SOMETHING. Not so much in this game tho; no matter what you do you only get Police/FIB cars/trucks/helis coming after you with intent to kill (YES I know you can get arrested, but that rarely happens because they usually kill you first). Needless to say the AI could be improved a great deal:
-The game introduced tear gas....why not have the police try to barricade you and throw tear gas? (BTW how could they NOT include gas masks in this game? makes no sense)
-The game introduced dogs...why not have them use police K-9s on you?? That would've been so much fun...
-The game introduced stun guns, yet no police officer or security guard ever use them; you get 1 star and the guns come out.
-It's disappointing to see highway patrol on the lookout yet they don't even react to you speeding. How about making them give you 1 star for speeding, and maybe ake it so that you can purchase trackers for your main cars? Well, that requires better AI...
-How about making the army, or even Merryweather agents attack too? Endless cops gets really boring, and considering that some acts the player commits are borderline terrorism I really don't see why this doesn't already occur.
-Why do police just drive straight into you even if you're in a tank? It's because the AI is simplistic
-Why do the police plow through regular NPCs without a care just to kill you? IT'S BECAUSE THE AI IS SIMPLISTIC
-Why introduce stealth elements if the game doesn't even follow it's own rules? I can shoot a lone officer from a rooftop 100yrds away with a sniper rifle w/ supressor attached, and I still get 2 stars instantly?? That ain't right.
Sorry for the long post, but as you can see I've given this some considerable thought, and trust me this is coming from a GTA vet. I'm at 87+% completion lvl for the game and my stats vs police are pretty damn good. It's not that the police are too hard per se, it's just the AI is too simplistic. Given the police are the main ever-present "enemy" in each and every single GTA game, it should be more than just hordes of cops with impeccible aiming coming at you with little difference in intensity. The game would be immensely better if they improved both aspects; make the cops easier/smarter on lower wanted lvl, and give us more variety and different challenges with a higher wanted lvl.