I don't have that problem with the clock not showing up right when I press the unlock button on my phone. When the screen lights up, the clock is there with no delay.
The thing I really miss is that the search button doesn't work on the marketplace anymore, instead, there's the on-screen button. I was used to it. But, on the other hand, when you search Bing for the name of an app, it searches the marketplace, too. Not the same thing, but it works when I know what I'm looking for.
Another thing I'd like is the option to have toast notifications for, well, notifications from the Me Hub (when someone mentions me on Twitter or writes on my Facebook wall) and a counter for the Me tile (instead of just the last notification). That'd be nice.