Yun 2...? They're in the same TRO. The Yun is for rapid commando insertions (though it isn't that subtle really), the Shun is for carrying infantry where you need them, en masse.
Regardless, the Cappies do get some lovely and interesting toys for sure. The Yun and Shun both are good examples, indeed the CapCon 3145 TRO doesn't really have anything i'd call a dud, expect perhaps the Mortis, though there are one or two weaker units (like the Vandal, which is a bit lacking i think, thanks to its terrible configs).
(Now they need a super-heavy siege vehicle thing like the FedSuns Destrier, with Cappie-twist to it (Stealth armor isn't probably suitable but perhaps quad-Arrow IV or something like that...))