The sensitivity on the hand tool while placing/rotating an object. Placed a chair wanting it to face east, it snaps to face south. Better give it a grab to rotate it then. Whoops, it's now facing north. Another slightly annoyed grab and it's back to south again. Want that plant to be placed diagonally? After a dozen attempts, perhaps. This might be a slight exaggeration, but it feels very wonky sometimes. It could just be me, although I recall it doing the same in TS1 aswell.
I often tend to rotate with the , . buttons instead of the mouse, and I make sure the mouse is completely still when clicking to place (mouse mat and big, steady mouse that doesn't move too easily on its own helps). If you hold down the button while rotating, the sensitivity goes up, it seems, so I select the item, let go of the button while moving and rotating the item, then click to place - instead of placing and rotating in the same go. That seems to help.
For windows and doors, it has to do with which way you're facing, I think (placing them while facing outside VS inside). They will rotate around to the other side if you nudge them a bit, but the "default" will snap them to whichever way you're facing (and don't ask me which is the "default" side, I always have to figure it out ingame... I'm pretty sure I often place windows the wrong way around )
Seriously though, the way you face does indeed help a lot with placement, as does having the walls cutaway or fully down and the angle of the camera. As for interior-exterior side, Maxis windows and doors tend to have their exterior on the correct side when placed facing inwards, with the exception of later EPs like AL and M&G. I believe this generally goes for all the generations of the series bar the 4th?