Weird as this may sound, I'm more a freshwater reptile person than a fish person... but I still have favorite fish! I absolutely love betta fish, specifically the plakat. Yes, the standard red, blue and black plakat betta. I also love the koi/galaxy plakat, and am getting one next year for my upcoming Walstad tank project.
I also have a soft spot for all species of gourami, but especially the pearl gourami and dwarf gourami. I haven't decided if I'll house gourami in the future, but I just love them so much. For me, the dwarf gourami have amazing colors, and the pearl gourami are really graceful and elegant.