It looks like a pretty complete kit, however, for what you would use I think it may be a little overkill and you could definately get what you need for a lot less. It looks like a nice kit but maybe a little overpriced/overkill.
When I purchased my Warn 12k winch on my last truck (about 14 years ago) they were running a promo and got the recovery set all in a nice Warn bag otherwise I would have put my own together a peice at a time.
For the most part I would have a snatch block, tree saver strap, medium lenght tow strap, and maybe an anchor chain. The "D" rings are great but you could get those at a Grainger or watch for sales at off-road stores. You should be able to put together a nice assortment for quite a bit less money.