Putting the Winch size aside, You should have 1 or 2 snatch blocks in your kit. WHY,.....because at some point you will need to use the winch in a less than ideal positional recovery. You won't have a straight shot to a anchor point, but instead be at a angle. This will cause the winch drum to wrap all the cable/rope on one side, causing either a JAM...or....a MESS. Using a snatch block or a shackle creating a shallow 'V', will help keep the cable more straight as it wraps.
Before I got my winch, I was involved in a recovery where I was one of 2 anchor points. THE SCENARIO,,,,,,, A Jeep with a trailer, needed to get out of a very steep hollow, with a sharp 90 degree turn half way up. Because of that, he could not just attach his winch line up above. The very steep climb,+ the turn, ensured that he would have to stop half way up (needed 2/3's the way for traction purposes) and redirect the line. The ground was slippery and somewhat wet (no traction), meaning he would slide uncontrollably to the bottom. What we did was create a directed pull, that would get him up far enough to hold the jeep/trailer while giving him a solid anchor on the road above (Me), and to one side(my trucks recovery hooks. By the way if he had had synthetic line, it might not have worked out, as the winch line even being directed, still was in the dirt in the middle 90 degree turn area. I had to use a 30 foot static web strap line as a long tree saver with a Clevis (pre winch/pre snatch blocks), with his cable being directed thru it to my trucks recovery hooks. This was a time before synthetic line became more common, and before the advent of soft shackles (safer) I grabbed blankets/jackets etc as line dampers in case of a problem. Made sure everyone was far back, and even being safety aware, I still had to remind some to stand further back, Something you would think would go without saying.
Everything worked out okay, and now years later, it is nice to have gear more attuned to safety, then was available at the time. Soft shackles are a big game changer. They allow for a wider range of options than just using metal clevis shackles. I would say that on these, bigger is way better than a smaller rating both for wear and safety IMO.
