Overall the zoo is pretty nice, but there are few ...

Overall the zoo is pretty nice, but there are few things I'll mentioned below of why I can't give it 5 stars.
They give a really good price on membership, so I opted to get a membership and all I have to do is visit two times with friend and I cover the cost of the membership.
The people at member services were really nice and friendly and answered all my questions. Unfortunately they make you come to membership services to pick up your membership card.
The gatekeeper was really friendly and so with customer service people and all of the locations we visited.
We went on the carousel and the operators were super nice, we wanted to go on the train, but it wasn't running till 4 and it was on the other side of the zoo, so we didn't make it this time.
Now for the reasons for the lower rating. If most all of the exhibit buildings would have had automatic doors I would have rated it 4 stars, but the only building with automatic doors we found was the manatee. This is not acceptable, all buildings should have a handicap electric door opener. We had a wheelchair and getting into buildings was very difficult.
With the current layout, it is not possible for me to rate it five star. The hills are way too steep, they are very difficult to get a wheelchair or stroller up and almost impossible to control going down I had to walk in front of the wheelchair pushing it back to keep it from rolling down the hill out of control.
This is a major safety issue that they need to find a way to address, if they could fix the doors I would give them a 4 star, but at this point I cannot give a 5-star due to safety.