I disagree, this is definitely one of your best episodes in my opinion. I have never watched Princess Tutu, so I have no idea who Femio is, but...eh, uh....he's definitely become one of my favorite abridged characters. I really hope he's a recurring one(if not, then the sassy green headed girl still makes up for it-ZORA!).
One thing that caught my ear immediately was Mr. Cat's voice. It sounded a bit more grounded and over all, more stable than normal, if that makes sense. Either way, even though he played a bit part, he was definitely better than most.
I liked the choice you guys ended up making for the guest opening with Hendrix's Whitney Houston one. The damn song's been stuck in my head ever since seeing your episode, but that's his fault.
There is something though, that I did not get. What "mime" are they talking about? The gesture he made didn't look particularly obscene...
Other than that...I don't think I have anything to add to this. Can't wait to see what lies in wait for episode 18ZORA!