Recently obtained the (Elite) Yellowstone Runabout hangar pets for my Sci, currently using my Vesta.
Pretty impressed - I don't PvP, so can't comment on their use in that scenario, but they're great in PvE; their tractor beam and chroniton torpedoes really spoiled the ISE Sphere's EPtE shenanigans - the Tetryon-Plasma engine discharge was fairly helpful too, although they had a habit of releasing it too soon, or too late, which had a rather limited (or in some cases no) effect.
Still - pretty pleased with them, and intend to purchase the Elite Peregrine's for my tac when gather sufficent Dil on said character.
Personal T6 Ship Wishlist:
Nova/Rhode Island class with Hybrid Pilot BOFF seat.
That is all. (guess this wasn't really a 'list' after all!)