i went paint pot crazy for a time and bought bare study, painterly, delft, greenstroke, moss scape, perky, rubenesque, fresco rose and rollickin. after a while i realized i didnt use a lot of them hardly ever so i sold/swapped delft, greenstroke, rubenesque, and moss scape (even though it's beautiful).
i find the lighter more neutral ones are more versatile, but that's just my opinion. i found delft and moss scape too dark to make them work for me, even as bases. but some other people totally rock them.
i recently also bought soft ochre.
i would say that bare study is a good one, and painterly or soft ochre depending on if you're pinker or more yellow.
ok, i've already typed way more than necessary. lol