8000lb capasity should be enough for most things. 9.5k would be better. Motors with permanent magnets are fine for occasional, light duty use and cost less. Series wound magnets are for heaver duty and more frequent use, faster line speed and cost more. Stick with a common name like Warn, Mile Marker, Ramsey. I belive that with a Shrock bumper you have to go with a winch that does NOT have an intergrated solenoid, it must be a remote solenoid. Wire rope was the standard for years. You must inspect for broken wire and replace when neccessary. You will get some small fray wires that can cut your hands, wear gloves always when handeling the wire. Synthetic rope is great, costs more ($250-$500), can get get cut-up/wear out from abrasion on rocks and frames, it also weighs less. You should use an aluminim hawse fairlead, which also weighs less, with syn line (big debate, I know of people that use a roller with out any problems)
Wire rope can have alot of recoil if broken under load, Syn has very little. Either way always use caution!