You can't be serious..... So many people do those things that it's blatantly noticeable when someone fails to do those things.... I honestly cannot believe that any woman would think a guy is trying too hard by demonstrating basic civil manners......Wow....maybe I just live in a happy bubble......
Hmmmm.... what percentage of the men you know would pull out a chair for you? I've had that done maybe a dozen times in my life, and I've always either nearly landed on the floor, or, more often, the chair ends up in a completely uncomfortable position relative to the table and it's more awkward to adjust it then if I had simply sat down on my own in the first place.
It absolutely can come across as trying too hard if the guy is nervous, especially if he cuts you off in order to get to the door first. Unless he actually knows how to do these things properly, it can feel very awkward.