This is not because something is not "conventional" that he is inevitably broken... Look at the flamberge, nobody complain about his animations.
I'm trying something else with the Long Jian atm, it probably gonna make everyone happy.
That argument doesn't really work due to the fact that you couldn't swing a Flamberge like a conventional 2h sword, it's large and clunky, hence the need to hold it differently and to swing it differently two, it's swung like that in order to hold control over it, imagine swinging it without that grip and with a normal 2h grip, you'd go flying due to it's length and size.
Swinging a large and heavy sword differently is a whole different thing to giving what is supposed to be a sword gripped with one hand a two handed sword animation.