PLEASE don't tell me to use powershell (for anything) I truly truly truly despise powershell. I'd be running Linux or DOS for the past 20 years if I wanted to use the more "powerful" interface of a command prompt.
Exchange 2007 had a lot of features missing in the GUI and they finally brought back some of them such as mailbox sizes. Please tell me we didn't take a huge step backwards with 2013.
The web management is painfully slow - it would be nice if they gave you an option of using the old console on 2013 - one so it would be easy to find things you've been doing for the past 6 years and two so it loads faster.