I just can't grasp the reason of instead of using the a cool-looking wooden staff from mystic origins powered by magicka, using a small little twig and yelling words. That's not how magic in the Elder Scrolls works.
Wand User: "I'll harm you...'
Staff User: "Go ahead, make my day."
Stealth, Weight, Speed perhaps. If you were a stealthy thief that liked to use magic in the form of staves/wands, what would you rather use when sneaking into someone's house? A small, relatively powerful stick that would lets you quickly whip out a silence spell so you can silently slit their throat, or a large unwieldy branch that hits things as you are sneaking around, hurts your back, and when you use the spell, blows up the house and half the guards come swords swinging?
Now, you may say "BLOW UP THE PLACE :flamethrower:" because you aren't taking this seriously, but you aren't taking this seriously. I'm sure "realistically" more stealth-fighters would use a wand instead of a staff for stealth situations, and it would go great in the off hand accompanied by a dagger. Think paralasys + throat slitting, which would be a very potent combo for a stealth fighter.
Now you could make the argument that the staff could also have a silence spell on it as well. Well then that's even worse for the staff, since you are basically doing the same thing but with added weight and inconvenience.
And you wouldn't necessarily need to shout words just because it's a wand, get your mind out of Harry Potter.
However, like stated, I would like wielded magic tomes necessary to learn magic and cast certain spells more than wands. That isn't the argument though.