I see that the old water tower is still there. I hope that they make some improvements to the look of that as well. Not to sound insulting to the WDWRR fans but it looks kind of cheap. Maybe my eyes have been spoiled by the DRR's water tower.
I have always been jealous of the Disneyland water tower, too. It would be nice to see an upgrade here. But because that area will have a circus theme, I don't imagine it will be too much different from how it is now, unfortunately.
The area in front of the station will be circus themed, but the station itself, according to the model at D23, has a very realistic traditional roundhouse feel to it. Its themed as though Casey Jr. has pulled up on a siding from the WDWRR tracks and a circus has been set up in front of the station. Unfortunately the model didn't include the other side of the tracks from the station, so I really don't know what they have in mind.