Locke has always been an interesting character to me since he had tried a lot more things a lot harder in his life than the majority of the characters before they all crashed: raised in foster care, he went through quite an unsuccessful parental re-union, he 'farmed' for a while, boxed his boredom later and had the will to go some nature excursion (desert walk?) on the other side of the world, despite the wheel chair and all (I'm excluding the emotional traumas to spare the sympathy). The survivor type he became on the island is cool as well, since he had only
read about such stuff--no real experience prior to the island. That deserves some kudos on its own now: not sure hunting boar in the woods alone for the group or keeping tracks at night would be a dance everyone can tap into especially after sitting on a wheel chair for years.
If you haven't got it by now, I really like this character
So you might think it's that, but the kind of trouble Locke causes has not been dramatically course-altering, altogether negative, or totally disastrous for the rest of the Losties I think.
1) finding and moving to the hatch was a Locke move that gave the rest a good deal of insight as to what the heck this whole thing might be about, wrong? Else, we were to watch another 24 episodes shot by the beach on God knows what trivial power-games Jack and Sawyer were going to get into. Give me the medicine, no you give me the girl, Kate go get some rulers!!Or More Sayyid-Shannon romance for worse. As for the hatch explosion, remember Locke's been challenged and patronized by Jack more than a few times about the button and numbers. If we are to take the 'Shepperd' as seriously as he wants to be taken, isn't it only natural that he messed Locke's mind and lead to Ben's involvement. ( I mean who would dis, bash or bully his ally in front of common enemy? that's only Jack's fault that Ben later used what he witnessed to manipulate Locke and Locke ended up blowing the whole thing, all puns intended)
2) As Ben explained by the end of 14th episode, the sub thing wasn't going to happen anyways, so Locke only provided Ben with the cover he needed. In that sense, there wasn't any real chance of escape anyways that Locke could have possibly ruined for Jack and Juliette. Ben did what Ben always does and tricked Locke and Others into thinking in a certain way.
Add Locke's healing and his airport-dream where he was told to help 'him' (Jack?) I think he seems to be a character quite apart from the 'savior', 'troubled beauty' or 'the charismatic anti-hero' types of the classical narratives one might associate with Jack, Kate and Sawyer. Sure these 3 characters are beyond cliches but the assoc. would not be far-fetched either) I doubt that Locke left the Losties for good to live with the Others or became their ally or something-- I'm assuming we'll get to see more about what the Black Box did for Locke and how..