I personally loved how you were never really doing the same thing 24/7. It was always a new experience when I woke up to go to work in the morning. This may be a bad thing at times cause we had to look for things to do, but really this allowed us to take time to improve the park.
What I wish was different
I don't have any huge complaints. My boss was always trying to make sure I received as much experience as possible, and was always very fair. He even managed to get seasonal workers a raise for every season they come back. It wasn't very much, but something is better than nothing. I guess my one complaint would be that our workshop was always a mess, but this is more a result of one coworker in particular than the park as a whole.
If you are looking to be a park ranger, learning some trades is probably better than focusing solely on the sciences. As a maintenance ranger I spend more time maintaining buildings (so plumbing, electrical, construction, etc.) and our vehicles/equipment. Knowing how to do these things would be more desirable for a park manager. If you want to be a forest ranger, science and law enforcement classes are probably more of the way to go.