assuming we are talking about a discrete design where you have an opamp running off of +/- 15 volt supply rails, you will get better phase noise performance if you have a small vco gain Kvco. That way, any stray noise pickup or ground loop noise will have a reduced effect on output frequency.
If you are using a monolithic approach, with a small supply voltage, like 3.3 volts, then your priorities are different. It is hard to actually tune to either the supply rail, or ground, so you have to guarantee that the vco can be tuned over the entire 1066 to 1600 MHz range with a tuning voltage of perhaps between 0.5 to 2.8 volts. You have to insure this is true over the following conditions:
1) long term aging/drift of the F vs Vtune curve
2) impedance load pulling
3) Power supply frequency pushing
4) operating temperature range.
In that case, you probably want a big vco tuning constant Kvco, and will have to live with the phase noise hit.
Rich