A couple of questions

[Jeff Kaos]

First: is there a way to re-spec you're skills in game? If not are there any reliable mods that will allow me to do this?
Second: Is it worth spending skill points in "lockpicking"? It seems like I'm finding pretty decsent weapons just laying around but I can't help but wonder what kind of goodies I might be missing in all the locked chests I see scattered around.

[mgsmith02]

Google Dead Island Save Editor. It can do anything you need with respect to skills.

[The Miszoq]

I've never heard about reset skill points (good to know) :)
For your question - metal chest have chance to really good weapon (even guns and even at the beginning). I heard that locked chest has better chance for higher tier (better quality, for example blue than white) than nonlocked chests, but is it that true?
I had better stuff from locked chest.