FS -
Chisholm Raiders: Their background is quite interesting, and both regiments are very skilled, though not as flashy as the Crisis Lancers or the Royal Brigade of Guards. In addition, I like their dedication to the FedSuns as shown during the defense against superior Combine forces during the 4th SW. After the FCCW, I'd choose the
Ceti Hussars.
DC -
Arkab Legions: The Legions are outstanding raiders and have a very interesting history, too. I like them very much. I also like some of the district forces, the
Dieron and
Benjamin Regulars. They have some very good regiments.
FWL - Prior the 4th SW, I'd choose the
Marik Guard. They are a highly motivated, skilled fighting force and known for bravery. Later, I'd go with the
Orloff Grenadiers, I guess, since they are a respected, well-rounded force.
CC - My favourit is by far the
Hamilton's Higlanders regiment. They are highly motivated, very dedicated and quite successful. However, like the Marik Guard, they were destroyed during the 4th SW. Alternatively, I'd choose one of the
Warrior Houses, though they're a bit mainstream.
LC - I definitively go for
Winfield's Brigade. They are a highly-mobile combined arms fast reaction force, very skilled, keen on raiding as well as assault missions and use lots of Medium Mechs. Paradoxical, they are still one of House Steiner's line units. Unfortunately, they were destroyed during Operation Revival by Clan Jade Falcon, but only after they kicked the Falcon in their lower backsides. Alternatively, I'd choose an
Arcturan Guards unit, presumably the 17th or the 23rd, or the
3rd Royal Guards for the post-Clan-Invasion era.