Para sakin, PSB Alpha B1 + NAD C315BEE o kaya CA S30 + CA 540A V2... lalo na kung magdadagdag ka talaga ng sub later on.
Kung vocals focus mo, Marantz PM4001 + Q Acoustics 1010i or Tannoy Mercury F1 pwede ren.
An alternate speaker for any of these amps is the Wharfedale Diamond 9.3. I love the 9.3s --- they can play most music genres without an issue.
The Polk TSi 100 + Dared VP-16 may also work for you, if you like the sound of tube gear (and can go a little over the 20k budget).
Siyempre depende pa ren yan sa listening area mo and yung sound preference mo. Kinig kinig ka lang and mix and match hehehe.