Jazz stuff relies on a lot of low level subtle details. I hated the whole thing until moving from dynamic to electrostatics. Now I can't get enough of it.
I can see why people will prefer Ella/Nina/ etc, they have a more impressive voice and can grab attention faster. But I somehow don't like their music (the music itself). Their stuff probably sounds better from more generic equipment, just like pop stuff are great playing on car radios (or even boom boxes). So before you hate Krall so much, try it with another rig and see. The speakers on your TV will not do any music justice (well, except may be country music).