Those who can't shake the cops well, that include using circle to hide in the back seat?
The problem there would be shaking them long enough to get somewhere that you can use circle to hide and have it actually work. And even if you do manage to do that, you have to deal with ctOS scans starting up almost immediately afterwards. Those seem to find you no matter what you do if you can't get out of the yellow circle before it fills up... and then the chase is on again.
It's still doable though, with a bit of luck. And imo having the thing to disable helicopters is a must. Nothing's more infuriating than finally pulling off a perfect focus+barrier move that wipes out all the cops chasing you only to have the fucking eye in the sky put 3-4 more on your ass again.
That said, it's still not as bad as GTA V cops. At least here you have hacking to get rid of them even if it doesn't always work out, and things don't seem to escalate if you take out too many cops without completely getting away.
As for the shooting compared to GTA V, you actually have to aim even with a gamepad. There's some aim assist of course, which can be turned off if you want, but it's still basically free aim. There's a strong version of aim assist that I haven't used, but I even with that I don't think it's like GTA V where all you had to do was hit L2 -> flick R-stick up -> boom headshot -> rinse and repeat. There's also a "focus" ability that is basically bullet time. Haven't used it much because I generally only use melee takedowns from stealth when I'm forced to fight.
I wouldn't recommend the game at full price, but I don't see myself regretting the $25 I spent on it. I'm at about 20% completion now, mostly from a LOT of side missions and about 75% of Act I.