I'm a genereous person when it comes to description. But I think yours are quite adequate, congrats.
About the element thing, well .. I suppose you could go with dual element: Wind AND Metal ... so that solves that problem.
Oh, and seeing as you're a Captain, please note that you are allowed to make a fourth tech, should you desire to do so.
Now, carrying on, though.
One question: Are these bills ... incredibly tough? Can they or can they not be broken? And what would happen if one DID break?
Tech #1. Adequate. I'm assuming you're not 'throwing them' but sending them out via some form of manipulation(magnetism or whatnot). You WILL have to state how many bills there are in the group that you send out, so that your opponent will be well aware.
Just a question though, when you send them forth ... do they just fly straight forward? And after they are repelled, stab into something, or miss their target ... do they regroup behind you?
Tech #2. ? The description was a little odd at some point ... ah, How can the blade portion be pointing at the enemy if the bill is spinning? Or do you mean spinning in a cylindrical fashion, such that the weapons are rotating like drills? I'd like a bit of clarification, just to be safe ^^;;
So, it takes one post for the 50 bills to surround the opponent and make 5 layers of 10 ... and THEN on the second post they start stabbing? Again, clarification just to be safe.
How long does the stabbing-fest last? Two posts? Three posts? Please add that in, unless the bills indefinetly stab the opponent, O.o;; at which point I would deny the tech if that was the case as it would be potentially unfair.
Tech #3. Okay, the box is fine ... but, this leads back to my question about the endurance of your bills ... really, I doubt the box would withstand a point-blank Gran Rey Cero and you would receive no damage whatsoever. I do not object to this tech, but it can't guard against some of the best attacks available in terms of raw strength. Please define the degree of power it can withstand, in your own words.
Also, just for clarification, when you 'trap' an opponent ... or even when you form this box in general. After the preperation time, is it instantaneous? Or can an opponent 'dodge' per se, from being caught in this box? Please clarify that, oh and also ... it only lasts ONE post? Whether it protects you or traps them? Just want to make sure.
Please address these minor errors before I render an approval upon this sheet.