We're also using Osmo's One Coat for most of our exterior, and loved it. It's German, and while they're not about to tell me what's in it, which is annoying, I have a lot of confidence in ecohaus, the pretty cool green super store in Portland (and Seattle,) to not import junk or poison. It also fits the very high German Toy Use standards.
For our floors we're using Osmo's Polyx Oil on our Settler's Plank Oak and vertical grain Douglas-fir that went down in Maxine's office and Jake's tower, respectively, as both of those just glow with an oil finish. I particularly like that you can replenish the oil finish so easily, which both of these floors will want. However our American Gothic Grey Elm, which covers the bulk of the main floor, is getting Vermont Natural Coating's clear satin interior polyurethane. I'm sorry, but that elm's pale soft color and texture just goes darker and more amber than we like with oil.
Hey you might be interested in joining a professional training on the polyx oil application on December 2nd as we do the tower floor. Email marcs@ecohaus.com.
There'll be barely any regular paint, as the interior wall finish is American Clay, but here's a lovely shot of Maxine brushing one of our European-style wall radiators.