Albums that have an albumartist other than Various Artists should show up under that artist rather than Various Artists. E.g. if I browse to Eppu Normaali and double click the album Paskahatun paluu: B-puolia ja muita harvinaisuuksia 1978-90, that entire album should be added, including the one track by Eppupopedanormaali, and not only the tracks by Eppu Normaali. Putting this album under Various Artists doesn't make much sense.

No, it doesn't make much sense, as Amarok itself cannot insert the Albumartist tag. I have the collection arranged by Albums and it's my fave sorting method. There are many feature requests around this topic. Check bugs.kde.org and vote for your favourite solution.