You and me both. I find it very annoying how I can lay in a beautiful habitat and put some wonderful, majestic animals in it and get almost no visitors going to see it. But drop a restroom or soda shop right next to it and suddenly the place is a huge draw.
I second this finding. I've started laying in exhibit-houses that have 4 to 6 exhibits, 1 restroom, 1 drink shop, 1 food or souviner shop and some visitor education stand in remotest parts of all of my zoos when I am building them, because those end up being very large draws for people and get them out to all the farthest habitats. I've done this in all 7 of my franchise zoos at this point and it's been very effective.
Another thing that seems to help is not having a lot of "dead end" paths that just go to one or two habitas and then go no further. Visitors seem to like taking routes that have connections further along, so using either loops or making sure to at least put many different things (multiple habitats and shops) to do along the dead end works better.
I don't know how much it's related to the above and how much is just other strategies in layout, but all of my franchise zoos also have visitor happiness at 90% or higher and 0 refunds most years. Which is a long ways from a few weeks ago where my largest ones started bleeding money and happiness. Not sure how much of the change is things changed in the 3 patches since then and how much is my redesign of a lot of the layout.