Couple of points which I want to throw my 2cents in on:
Management:
SWOs do a lot of management, true. But the DISBO on my ship has far more people than any other DIVO. The title is actually ASUPPO now, as he's the "DIVO" for 3 divisions. That said, he has much less interaction w/the troops than SWO DIVOs do/or should at least.
Redundant School:
I haven't been through an MBA program or supply school, but I highly doubt they will be teaching you redundant stuff at Supply school. Pretty sure it will be focusing on teaching you how the Navy supply system works, and how you will be expected to utilize it. And yes, a paid Navy school is probably going to be much less work than what you'll do in the fleet...for the same pay.
Responsibilities:
DISBOs handle ridiculous amounts of money from the get go.
As SUPPO DHs, they tell the CO how much money he has left before the SUPPO has to ask for more.
Warfighter vs pussy argument:
This is kinda a bad argument IMO. To be honest, the SWOs aren't doing much warfighting. Not that it's not important, but we're not getting into gunfights all the time. And what little there is to be had is a lot about being in the right place at the right time. If getting into a no shit shooting war is your goal, there are better ways to go about improving your odds.
I would also throw in another "pro" for SUPPLY...you can go to any community, not limited to surface.