Paavoharju have a couple of beautiful albums.
Other ambient stuff i'd recommend, albeit fairly obvious cliche choices, are Global Communication's 76:14, anything by Susuma Yokota, Stars of the Lid, Biosphere's Substrata and Lifeforms by FSOL (a tad dated i suppose). Loscil is a personal favourite, especially Submers and Plume.
Almost forgot Murcof and Gas as well (the recent Gas box set is well worth it. In fact, there's tonnes of other gems on Kompakt).