I liked it, if for no reason than the campy "Let's dress like Elvis to break into the Casino" bit :-)
It was probably one the first episode where I was OK with the new boss... until now she was coming off as kind of a witch towards the "team" (particularly Castle).
Here she explained herself somewhat... Castle's good but he throws a bunch of theories on the wall until one of them sticks. She's correct that cops on't have time for that... but in practice I imagine it still happens. It looks like a lover's spurn, it now looks like it's about money, now it looks like it's revenge on something, oh it wound up being about money like we thought earlier
And Kate shouldn't be using that as a crutch, she's good on her own.
I like that more than "you're not a cop, you don't belong here... even though you've done a lot for the precinct."