imo, Lu is NOT a singer. In one scene when she was rehearsing, I thought she could benefit from REALLY NEEDS some vocal lessons. Then I realized, she'd probably be offended by that suggestion, because, look at how fabulously she's doing! Ok, she does have a stage presence, I'll give her that, and she seems to be comfortable working the crowd -she THRIVES on being the center of attention, (jmo), and they enjoy her. The show probably is, in person, very entertaining, if you're into that. I think some of the criticism comes in when she doesn't differentiate Cabaret Countess from everyday Luann. She expects the fawning and adoration from Everyone, and her friends (aka The Little People) have had enough. They supported her at the beginning, but can only put up with so much.
Before anyone brings up Beth and incessant SK product placement and Ramona and her products, just remember, we were just as annoyed then too(if not, more so -looking at you Bethenny who had a whole trip revolve around product placement), so this is not really unfair judgement, at least as far as I can tell.