I've recently been looking for a good pair of tac gloves myself and have done an extensive search on the net. The Hatch SOG Special Operations Glove seems to be the best thing I've found. Here's a link to an independent SWAT review of how good they are:
http://www.hatchcorp.com/lawpages/sog100_test.html
Made of Kevlar with goatskin palms, so I don't think thorns will be a problem. Same or better heat protection and dexterity as Nomex flight gloves, but stronger and better fit and better design to prevent tips of fingers coming unraveled. And the trigger fingers can be permanently removed without worry of the rest of the finger coming unraveled. I also found one website that had a version of this glove where all the fingers could be removed. Also comes in a gauntlet or non-gauntlet shorty version.
here's a link to the lowest price I've found on this glove that will save you $10 to $25 over everyone else.
http://www.hatchcorp.com/lawpages/sog100_test.html
There are a bunch of good deals at this website. Check out the Cold Steel knives, especially the Cat Tanto for $4 each.
Hope this helps.
Semper Fi