Yeah, Felicia's character still seems a little mean-spirited (which may just be how it's been written) and not enough of a buffoon. Trace always came across as buffoonish, and forever plagued by his bumbling sidekick (who was entertaining in his own right). Trace apparently based Dr. F on a guy who used to run a comedy club where he and others performed.
A big part of the success came from the fact that pretty much all of the early MST3K crew were big into improv and some standup. Felicia Day, as far as I know, isn't. That's not a dig against her, mind you. I mean, I'm sure she's DONE some improv, but I haven't heard of her coming out of an improv tradition. Patton is a standup and a masterful one at that, so he just GETS comic timing. Actually, that's probably not quite right. Patton "gets" it on an instinctive level, I suspect, but he also has seriously practiced his craft for decades.
I'm hopeful that things improve, though. After all, the show itself was nigh unwatchable in the first year (and if you go back to the KTMA days, it's like a whole other thing). Seriously, try watching back when Josh Weinstein was on as Dr. Erhard in Season 1 back when it was on the Comedy Channel (before it became Comedy Central). His Tom Servo is funny, and Josh himself is actually a freakin' riot (and a decent bassist -- too few of those out there) in Cinematic Titanic stuff, but their riffs were slow, Trace was doing "baby Crow" voice, the movies were REALLY bad, and it just...well, it took a while for them to find their groove. Season 2 things improved, but by Season 3 they were firing on all cylinders, and that stayed true throughout the rest of the show.
Mary Jo's Pearl was...irritating. I really didn't enjoy the character. SHE'S funny, but the character was just...eh...it never quite worked for me. Her guest spots in Season 6 and 7 were better. It also didn't help that Sci-Fi channel required them to have a "plot" early on for the host segments. I think that actually hurt some of the host bits.
Anyway, my point is that I think the show will likely improve if it comes back for a Season 12. I really do hope it does. RiffTrax is great and all, but Mike, Kevin, and Bill just have a different...vibe to their riffing. It's not better or worse. Just different. I really enjoy Joel's style and his influence, which is why I went to every Cinematic Titanic show I could make it to, including the final one ever (which was a double-header). So I hope he gets to keep doing what he's doing.