With Deadpool becoming more and more popular in mainstream Marvel comics, I've been looking at the character lately and considering his place in the Marvel Universe. With the similar powers and MO, one might be tempted to say he is most like Wolverine. He is utterly deadly with nearly any weapon, as far as we've seen pretty much indestructible (if he has a limit we have not witnessed it yet) and completely insane. He is at the very least a minor threat to every living being and at worst an unstoppable killing machine if he put his mind to it. However, it is that last point, his very instability, that lowers him from threat to annoyance to most of the players concerned.
He is vain, narcissistic and completely self-absorbed. As such, he takes that great power he wields and only uses it as it amuses or pleases him. To his favor, he fancies himself a hero, and is wont to stradle the line between neutral and good more often than not, swinging whichever way will make him look the best. The fact that death and destruction follow in his wake only speaks to his methodology and not his intentions. These aspects combined, he is less hero or villain and his blowing into town is more akin to a force of nature, a hurricane sweeping through or Galactus wandering through the cosmos. Granted, you'll probably have an easier time reasoning with the hurricane.
The ability to break the fourth wall and more recently the inner dialogue going on between voices in his head suggest an almost omnipotent presence in the comic-verse, or at least a higher awareness, on a meta level, though not a particularly useful one within the scope of the comic itself. This, coupled with the immense power and penchant for acting on a whim, leave Deadpool in the position to be a better example of a Trickster God than Loki has ever been used.