Numbers don't mean anything other than a stand in for a concept.
As expressed above, gruntala, the difference *IS* in the numbers, but the numbers are really just a concept. "Tank, or DPS" is simply a matter of numbers sometimes. How an ability is useful is based off of them, but really, the only thing that changing a number does, is changes how the spell works indirectly.
If we dropped the damage to like 50 and stun to 2.5 seconds, it'd be an impressive, heavy hitting CC; if we dropped the stun to 0.05 and damage to 350 damage, it'd be a strong spamable ability probably, great for interrupting channeled abilities but unable to stun for real.
All of it comes down to numbers, yes, but the numbers have no meaning outside of whot yeu want an ability to do.
Simply stating "High damage, low cooldown, and a microstun" is all that's needed, so long as we know roughly where they should be in relative terms to the standard defaults for similar spells of its' kind.
Note that even a tiny tweak here and there can have massive effects; decrease the cooldown by 1 second, but don't change the mana cost... the champion, once pretty easy to handle with minimal regen gear, now finds themselves needing a meki pendant to even start the game with. The adjustment was small, but it increased the rate of mana consumption vs mana regeneration by a large value.
Tiny things like this aren't really understood without intensive play testing for weeks on end. The difference between OP and UP is really very, very small in many cases.
In short, most people on here can't even begin to grasp the rammifications of just how powerful their abilities really, truly are... and to be blunt, the people reviewing them don't know any more than the people writing them.
Adding numbers will not do any more than give yeu a ballpark figure. And honestly, "high damage" is exactly that... a ballpark figure. Except, in the hands of someone who doesn't know whot they're doing, we now know they actively INTEND for it to do "high" damage. The guy who just lists that it does 500 damage, may simply have no idea whot they're doing and thinks that's only medium or average.
As such, I'm not too picky on numbers, so much as I am interested in concepts. If it's FUN, then YAY! If it's unique, then it's even better! If it's unbalanced and needs number tweaks... well, whotever. It's very, very rare I even complain about numbers, unless they're blatantly senseless... like someone earlier who made a DPS with a "on next attack, resets swing timer" ability, with a 16 second cooldown, which goes against the purpose of an ability that does that since they're meant to work in tandem specifically with a trinity force.
Anyway, it's not that big a deal, but it shows they didn't understand the purpose of why those abilities work the way they do; if they'd said "long" cooldown, I'd have known just as well they were having problems with it.
But yeah, I digress. The whole point of this is that yes, numbers can be important, but they're honestly just a stand in for a concept. So long as yeu get the concept, the numbers themselves are irrelevant.