The Shias (who belong to another branch than Shias in Iran and Lebanon, who are also two different branches) of Yemen are very moderate in practice (as for in theory; well their slogan are "death to USA, death to Israel"), they have couped the government through a broad multi-religious northern tribal coalition. They're very hostile toward Al Quada. But they also claim some Saudi border areas, which SA occupied/leased in the 1930ties. They're also very hostile toward Wahhabism and Saudi preachers/missionaries. The government and the ones before have de facto been a Saudi vassal (even the old president who was a Shia).
The "death to the USA" thing aside, the Houthis really don't sound all that bad.
