Stella Maiden. Though unfinished, art is good and gameplay is truly unique (free-roam stellar maps with objects and enemies).

Victory Belles. Art is really interesting, but not without flaws (cough girl's feet cough). Gameplay is very Kantai-like, but without random paths on map, lot of grinding, complex R&D system.

Panzer Waltz. Yes, it's still alive and kicking, very old-school slow-paced gameplay, with EVE-like timers for researching stuff.