Variety is the spice of life. I'd recommend mixing up audiphile standards like Dianna Krall, Anne Bisson & Miles Davis with some jazz (Tony Bennett Duets, 'Red, Hot & Blue - A tribute to Cole Porter'), Classical (Mozart, Bach - Goldberg variations,
Tchaikovsky - 1812 Overture etc), Operatic (Andrea Bocelli), world (Deep forest,
Dead can Dance, Bjork), folk (Joni Mitchell, Bob Dylan), female vocalists (Tracy Chapman, Eva Cassidy, Sade) Classic rock (Dire Straits, Pink Floyd, Crosby Stills Nash & Young, Beatles), plus some 80's easy listening and ballads & you should be covered.
