some weaponskills are meant to be single target because of heavy damage, well not in FFXIV, but almost all "final" WS(cap went by like 5x) in FFXI were single target. About the modes, when i look at it, i get the idea it looks like a skill u would use to make ur attack be better for a short time rather than actual mode.

I think it would be nice if they all had 1 mode but uses a skill that would give them different type of style(Frontal cone, Line, 360 etc) for a certain amount of duration.