I don't know about anyone else, but it's kind of upsetting when a show has a fairly good plot going, but is usually too short and the plot ends up getting choked by fan service. Not to say that one should get rid of all the fan service (

) but I wish they'd make it longer to realize the developing plot more.
It is possible for shows with a good amount of fan service to last a good amount of episodes. (Ranma 1/2, Mahoromatic)
The shows that I'm specifically addressing (because I've seen the recently) are Cosplay Complex, Jungle de Ikou, and Amazing Nurse Nanako.
Cosplay Comlpex was good and funny, with plenty of fan service, but just as things were starting to get interesting (*spoilers* Yes I'm too lazy to do a tag. When another character is introduced (it's been a few months) and she has a similar cotume shapeshiter buny girl thing, and all the suspicions of the main character being a great legendary person, and then poof, it ends. Why? Nothing was resolved!)
Jungle de Ikou also had some fanservice, but it wasn't quite as bad as Cosplay Complex. JDI started out midly interesting, got silly at points (anyone see Ahem do "the dance"? Silly and creepy all in one package.) adn finally at teh end really hinted at posilble future exploits. Then, it just up and ended. I was starting to like it too. Mii was almost an anti-magic girl (you can have an anti-hero, so why not?), and the talk that there are other legends out there meaning the possibility, if not leaving it wide open, for a continuation which has yet to see the light of day. (though I heard rumors that a TV series may be made, but don't get your hopes up)
Amazing Nurse Nanako had more fanservice than JDI, but less than Cosplay Complex (are newer shows desensitizing us?

). The show of course spent time being silly and reveling in it's own silliness for a good amoiunt of time, but out of the the three titles, this one had a much darker background story. The theme was genetic engineering and the aim for immortality. (*spoilers* However when this series got serious, it was actually SAD. Yes, a title that has a reputation for bouncing flesh, was actually tear jerking at parts. Nanako, though lighthearted and sometimes dimwittec, has a deep saddening past. Nanako is in fact a clone, the third clone to be precise. The original Nanako was born in 1920. When she turned 20 she became strangely ill and died. The current head of the Ogami family at that time somehow managed to clone her (in 1941?). However that clone too died at teh age of 20. A second clone was born in 1962, and she met with Kyoji (the current Dr. Ogami when the series opens up) when she was 16 and he 7 in 1978. he becomes emotionally attatched to her (she was very kind, almost an entirely different personality from the current Nanako), but she too dies at the age of 20. Kyoji had made a promise to cure her, but it's sad to see him begging his dad to help when Nanako's body is being put into the hearse. At the end of the series (longest of the three at 6 eps) Kyoji fianlly manages to whip up some gentic "cure" but the series ends before you see if it worked (the current Nanako is 16). But things are left open, one character escapes with data that could seriously hurt the both the Vatican and the U.S. reputations(they were working together on a blackops project with an alien being. The U.S. wanting to create biological weapons and the Vatican wanting to clone Jesus.) saying "Now all I need to find is a buyer". the last we see of Kyoji, Nanako, and friends is them being sent to research duties on the Skylab space station.)
Plenty of possible ways to continue, but ti just ends
(and yes, I just finished watching Nanako not too long ago, hence it being the most freash in my memory of the the three titles)
Did anyone else feel the same way? That they'd like to see more of these series, hopefully fleshing them out enough to give a more satisfiying end?