1.75 will do you fine on the road. I'd even think about narrower if your tyre choice is available in it.
Width really shouldn't make much difference in itself. What will make a difference is changing to a different tyre (brand, model) and the rims you are using. I've got ones I can do with thumbs alone and some that are complete pigs to get on.
Width will make a bigger difference than brand.
Wouldn't have thought it would make that much difference within the range the OP is talking about. ie. 0.25" either side of the originals.
One of my bikes gets switched between Schwalbe Marathon+ and Marathon Winters, same size, same brand, same rims.
The winters are a fair bit easier to get on and having read threads on here in the past it looks like some rim/tyre combinations are harder to fit than others.