I came from the OG Droid and never had an HTC phone. I thought Sense would slow it down but it runs smoother than the Nexus. IMO. I'm starting to like Sense. They put a lot of thought into it and it looks great.
People like widgets - one of the main reasons to choose Android over IOS. I don't blame Google for not putting more effort into some of their widgets in the stock rom, but at least HTC steps-up to fill the void. The problem with 3rd party widgets is Google locks-down some of its API's so tight (exchange/email, and now Gmail among others) that you have to hack (which is becoming increasingly harder with the higher security) to be able to have 3rd party widgets access.
I mean, IMO Pure Messenger widget is the best app out there. It gives you a truly combined inbox for ALL messages (calls, 3 gmail and 3 exchange accounts, SMS and facebook and twitter if you choose) - ALL your messages on 1 screen with a nice, scrollable widget. But doesn't work on ICS unless you mod the Gmail and Email apk's to turn down the security (and not easy to do for novices like myself).