Hmmm' as far as ecchi, There's one that came out last year (with a 2nd season coming out this year) called Seikon no Qwazer which is a strong ecchi supernatural. The TV series is censored and is moderately ecchi, but the Director's Cut (DVD) is uncensored, and while it isn't full hentai, it gets a little close every now and then. I have most of the first season and 2 eps of the 2nd (all Director's Cut but the censored version is available via Bittorrent as well) I have only watched 2 eps so far (still in the process of torrenting the first season with 5 eps to go). I'm almost certain that it hasn't it's been released in the west yet, so you'll have to get it via Bittorrent, or DDL.
Classic ecchi (from the 90's) would be Labyrinth of Flame, and the Eika OVAs and movies, both of which have been released in the west .
Labyrinth of Flame is a hilarious OVA, it's about a half-baked movie actor who pictures himself as a samurai hero, and who somehow manages to become the sometimes boyfriend of a sexy martial arts princess who is also extremely jealous (and who has an ulterior motive for getting together with him to begin with). Needless to say he's always on the verge of getting his head handed to him on a platter when she gets jealous, and she gets jealous quite often because he has constantly roaming eyesT.T, even as far as the bad guys (er' girls), and a wayward scantily dressed CIA agent. In the end he does become a little bit of a hero, but just a little bit...
Eika is a well known ecchi adventure OVA series (and movie) about a treasure hunter/govt agent/martial artist who takes on the bad guys (and girls) and their scantily clad henchwomen in an endless array of battles with miniskirted bad girls falling left and right (it's been at least 5 years since I last watched the originals, so I might be a little off on the story line, but I don't think so). The western version even had a panty flash counter for the first ep (think it got up to about 125 panty shots just for ep 1). Year before last the series Eika R-16 came out, it's about Eika when she was first starting out as a treasure hunter at age 16) and it's not as ecchi as the earlier series are.
A recent series that is ecchi but not as extreme as Seikon no Qwaser and is really good is Rosario + Vampire (one of my personal favorites). It's an extremely entertaining series (2 seasons) about a human male who somehow manages to get into a school for monsters (if it's found out that he's human, it's instant death for him). He decides to quit before he gets killed, but then he meets a beautiful girl named Moka and instantly falls in love with her and decides to take his chances and stay... thing is this is a school for monsters, and so that makes her... no matter how pretty and sweet she is... a monster.
For some reason she isn't the only girl attracted to him (apparently he smells just like a tasty human... hmmm' I wonder why), and so he slowly comes to realize that he's a wanted man... thing is do these girls want him as their boyfriend or as their dinner? Moka possibly wants him for both because she's a vampire, and she just can't resist that delicious smelling blood, and he just can't resist those gorgeous mini-skirted school uniforms... until the girls start trying to chew on him!!:relieved:
Oh' and I'm also getting the Rosario + Vampire manga (also 2 seasons) which, of course, has a lot more to it than the anime, but both anime and manga are excellent!!
Slice of life: all time classic, Love Hina, the tale of an ecchi loser who winds up as the landlord of an all female boarding house and who turns out to be practically indestructible (thankfully because he's always getting pulverized by one or the other of the house residents because he's always catching them in various stages of undress or in the onsen) and who eventually falls in love with one of the residents. He's also a ronin who has failed the entrance exam 3 times to get into the most prestigious university in Tokyo, and who makes a deal with the residents of the boarding house (including one who is trying to get into the same university as he is), pass the entrance exam on the next test date... or give up being the landlord and leave. Well things never happen like they're supposed to, and before it's over all kinds of weird things wind up happening! I never get tired of watching that one.
Another really good one, and fairly new (licensed in the west) is Genshiken, the story of an otaku club at a Japanese college, and all it's quirky members. The handsome otaku who has a ferocious (but gorgeous) anti-otaku girlfriend who still winds up hanging out at the clubroom almost everyday just to be with her boyfriend. The mysterious club president who no ones knows how long he's been at the college. The otaku who always manages to say the wrong thing at the wrong time and gets his head handed to him by anti-otaku girl. The kind of slow guy who also happens to be an aspiring mangaka and extremely good artist. The guy who's a natural at making cosplay costumes for girls. The female cosplay loving otaku who's always wearing the stuff he makes, and always trying to get anti-otaku girl to cosplay with her. And last but not least, the easy going otaku who sometimes infuriates anti-otaku girl because he's too easy going. and that's just the first season...
In the second season a couple of new members show up, first is a guy that's so irritating that even the other members don't like being around him, and he actually manages to get punched out several time by anti-otaku girl for managing to say and do even dumber things than the first idiot. Next is another anti-otaku girl (or so she claims) but for some reason still joins the club, and she's an aspiring yaoi mangaka (which she tries to keep from the other members) and who seems to have a thing for the easy going otaku, or maybe it's that he has a thing for her...
One of the points of interest is that there is always an anime playing on the TV in the club room, and this anime is called Kujibiki Unbalance. Apparently this anime became so popular with the fans of Genshiken that the producers decided to actually produce it, and it is available on DVD (it was also licensed in the west).
The gist of Genshiken is that it follows the members through their college years, with them leaving the club one by one, and close to the end you find yourself wanting it to not end, because you start to get the feeling that you'll be the only one left... T.T
The last one I'll mention tonight is Hayate no Gotoku which has 2 seasons, it's about a high school student that's so unlucky that his parents refuse to get a job and keep borrowing money from loan sharks to invest in get rich quick schemes which after they blow it, he has to work to pay back the loan sharks. After borrowing a huge amount of money... and blowing it as usual they really screw him over, they leave him with the debt and split on him, and the loan sharks come to collect... since he doesn't have the money to pay them back, they tell him, get the money in 24 hours or he'll be sold... dead or alive...
Deciding to find someone rich and kidnap them for ransom (he won't hurt them, he's loathes violence) he just wants enough money to get the loan sharks off his back. He stumbles upon a spoiled rich middle-school aged girl who gets bored at a family Christmas party (and decides he's going to kidnap her), but instead winds up giving her his coat because she left the party without one. Things happen and somehow he winds up being hired as her personal butler, and that's when the fun really starts... by the way, like the guy in Love Hina who's indestructible, this guy is indestructible too!:l
