Vickie is good, but banned from ELO. Don is decent, more or less worth the 5 stars. Lyse Teria is decent, but is collector and unavailable to most people. Ottavia is not great, just ok. Everyone else in the clan sucks for ELO, for having either low power (4 and below), or ok power, but crappy damage (3 or below).
Without Lyse, you end up with Don, Ottavia, 2 other guys that are either practically free wins for your opponents (Like Mort Bax/Zodiack/Lino Borsa), or guys that do very little damage (like Pino). Even with Lyse you'll still have trouble finding that one last card for the Montana side of your deck.
Another reason why they're not considered that good in ELO is that the Uppers have almost the same clan bonus as them, but the upper have generally stronger 3/4 star characters.