Well, Eien no Aselia, the prequel of Seinarukana, has a fair amount of gameplay, and it's all-around a fantastic VN, easily my favourite. I'm looking forward to the translation of Seinarukana, I want it in English to be able to fully enjoy it.
Other than that, I found Wizard's Climber pretty fun. It's pretty short but has a good replay value, even I played it through 3 times to see different endings, and I still intend to play it once more when I feel like it again, because the ending I really want requires several playthroughs. <.< I'm also planning to eventually check out Bunnyblack 1 and 2 by the same producer, Softhouse Chara, they sound like they'd be fun.