First of all, LeBron is definitely in the mix, as would be AD if his team miraculously made the playoffs and if Westbrook is in the conversation. Second, Harden as you say has a very similar statline to Westbrook's except he is doing it significantly more efficient (several percentage points better FG%) and way less shots than Westbrook to put up 2.5 points less. Has the better record right now too.
LeBron won't win it though because he's playing with Love and Irving who are both beast players. When you compare James and Westbrook's stats, they're both playing 35 minutes with James having the better FG%, but that's because he's in the post more. Westbrook averages more points, more rebounds, assists and a better free throw % than James. So... yea.
Sure, KD is shooting damn near 60% from the field but fukk that. He shouldn't win it because he's playing with Thompson, Curry, and Green so of course his stats are going to be ridiculous because the defense can't hone in on him like they want to. Plus Westbrook is averaging more points, rebs, and assists than him as well. Despite shooting 57% from the field, KD is only shooting a little bit better than Westbrook at the line. So... yea there's that too.
Anthony Davis is averaging a double-double while Westbrook is averaging a triple-double. I'd rather have the trip-double player win MVP than the double-double player. But even if you say the double-double player is more effective than the triple-double player, Anthony Davis won't win it because his team is trash @ 7-12 right now and DEFINITELY aren't making the playoffs. Plus he's injury-prone as well so he may or may not even make it through the entire season.
Harden is slightly more efficient, sure. But he has a slightly better team, so that makes sense... But he's not averaging a fukkin' triple-double, bro... Harden's only shooting slightly better from 3, slightly better from the line, slightly better FG%, etc. But he's significantly larger than Westbrook and Westbrook is still out here beastin.
So give me Westbrook for MVP.