Thx, Ryll, though going through the latter half of your recommendations, it´s rather romance-heavy. I´d really like something with more of a true "group dynamic", where there´s not necessarily one main character, but several equal individuals. Maybe including Clannad as an example was stretching that idea, my fault.
So, really, when I make the above examples (Ano Hit Mita Hana, Bokurano, Genshiken), it´s how this group of equal characters are working together/against and interacting with each other. All that set in a rather realistic presentation that, however, is allowed to contain unrealistic elements (taking Bokurano as an example: Sure, there´s this crazy mech-battling going on, but it feels incredibly believable and is done tastefully. Unlike, say, full-on fantasy/scifi-anime like Gurren Lagann.).
I thought about including "Welcome to the NHK" as an example, too, but then I came to the conclusion that it didn´t actually feel realistic enough to me (the whole "cute girl approaches neet out of nowhere ... yeah, sure ... in our dreams!).
Also, I´ve already seen Itazura na Kiss, Planetes, Kanon and True Tears. I cannot remember the True Tears-plot, but I wouldn´t call the others fitting of what I´d like to see. Kanon is way to Harem-esque, and Itazura and Planetes are missing the group-dynamics between equals. Again, thanks for your posting, but it wasn´t really what I was looking for, maybe I wasn´t clear enough. Sorry!