IMO, Confed's ugliest ships-
Fighterwise-
The Thud (looks like a Sabre after a visit to a chop shop, with any and all aesthetically pleasing pieces removed)
(On a side note, and I'm sure there will be some disagreement on this, I always thought the Dragon looked like a space-going minivan with wings (especially from the back)- which just doesn't seem to fit with how what is probably the most tricked-out fighter in the entire WC universe should look)
CapShips-
The Ranger/Concordia Class (and to a lesser extent, the Vesuvius)- Just not a fan of a carrier that looks like a shoe box with engines strapped on the side, especially given the distinctiveness of the pre-WC3 Confed Capships (I totally dug the '60's style tail fins on the Confederation class, and the super structures on the Confederation and Bengal that looked like they were lifted off of a nuclear submarine
)
Kilrathi-
The Dralthi IV (YUCK) (Yeah, WC3 decided to branch away from the first two games with an asymetrical Kilrathi design, but a flying disk type fighter (Dralthi) was just never meant to be asymterical, IMO)
Ignoring the "shoe box" qualities of the Bhantkara (see above), I'd have to go with either the WC2 Fraltha, (kind of an amorphous blob with fins) or the WC1 Sivar.