I took a lot of buses last year, but you have to keep some things in mind:
I am very disappointed GenCon is not setting up a shuttle service. Downtown hotels are severly limited and parking around the convention center is very tough. Last years shuttle worked out very well for us.
I'm glad the shuttle service worked out well for you last year. Unfortunately, the majority of feedback we received from attendees regarding that service was, not as complimentary as we would have hoped.
I can tell you that I personally use Uber a LOT when I come to town; it's cheap, fast, and generally very reliable. I've even used it to go from the JW over to the Crowne, when I've been particularly tired and pressed for time.
When you leave your hotel in the morning you are very likely to see other gamers leaving as well; definitely talk to them about sharing a taxi or an Uber.
Marian McBrine Event Coordinator Gen Con LLC