You can't go too big unless you run outta money.
If the amp ratings are single line pull, using a snatch block will cut the amperage draw by maybe 1/2, allowing for smaller cable.
For a winch that is used all day I would want the max amps....large cable.
For a winch that is seldom.....if ever used, I'll go w/ smaller cable and just take more time, like using it 20 seconds out of 200.
Rich
'01 31' Rexall Vision, Generac 5.5k, 1000 watt Honda, PD 9245 conv, 300 watts Solar, 150 watt inv, 2 Cos 6v batts, ammeters, led voltmeters all over the place, KD/sat, 2 Oly Cat heaters w/ ox, and towing a 2012 Liberty, Lowe bass boat, or a Kawi Mule.