So I'm having some issues with a band member.

So I play drums in my band. However, I've been playing guitar for a long time, and have studied music theory and songwriting extensively. Our singer has a great voice and is decent at guitar/songwriting, but usually whenever we write i either write the bulk of the lyrics, change the lyrics he has written, or am adding new parts music wise (there was a time when I was writing all of my guitarists' parts for them). I don't do everything in the band per se, but I probably do 40% percent of the writing, he does 30%, and the rest is kinda split between the other guys.

We've been having a lot of conflicts lately, namely because he's asserting control of the band when he really doesn't have a good idea on how to run it. I shoot down a lot of ideas, namely because I've done my research, and have common sense (he wanted to get a DVD of the band professionally done for hundreds of dollars when we have a friend who has done them professionally and would do it for free). He's been trying to boss me around when it comes to the sound or the music, and I buck him on it when I feel he's wrong (and I always give him a logical reason why I think he's wrong). To add to this, I've been getting frustrated at shows because he'll take ownership of a song that he didn't necessarily write ("hey guys, I wrote this song a week ago," when I wrote half of it.)

On top of this, recently our mentor (he's not really a manager, but a music pastor we go to for advice) has said our band only needs one leader, and he should be it. The problem I have with this is that he simply doesn't know how to lead a band effectively (whenever he plans practices, he's late and at least one person won't get called, when I do, I'm early and have all the material ready and make sure I've called everyone at least a day ahead of time). Also, the fact that he would be the leader and, as our mentor put it, go through with his vision of the band would imply that he has done the bulk of the work for the band, when this isn't the case (I freakin named the band, I approached HIM about playing in a band, I completely rewrote his songs, and completely wrote some of ours.)

Just wondering if anyone has some advice.
one way to go about it is to let him to try and do everything by himself, if he doesn't figure it out then, punch him in the face(figuratively) and rationally explain it to him
and make sure he knows what he is doing wrong(but dont be an arse)
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We have an easy solution to that (which we use ourselves).

There is no leader per se. Each member has his specified area of main work, one does most of the internet and general pr stuff, one does most of the writing, one does most of the gigging arranging.

But noone acts entirely on their own. All ideas are passed through the members, and if one disagrees, he can state why. If it's a valid reason, the original 3 members decide.

Noone has the right to claim something as their own work, everything we do is done by the band.

Edit; as you might figure, it's kinda a slow process, but it works, and there are never any big disagreements between the members.
hmmm.... sounds like he has a case of LSD (Lead Singer Disease). LSD is when your normally cool frontman/singer turns into a complete dick and tries to control the band. examples of singers who have contracted LSD are Axl Rose and David Lee Roth. Normally, they either take total control of the band which becomes a rotating door of members, or he goes and has a failed solo career.

let him be the boss until he f*cks up bad. then, show him that decisions are to be made by everyone.