Greetings,

many people aren't sure, what staff to choose. I have done a lot of testing during the last few days and want to introduce the results to you. Warning: This text is a bit longer, so only read, if you're interested in using staves.
I've tested with VR14 staves, blue quality and without traits on them and made sure, to always fight against the same VR12 enemy.

Fire staff: This is still the favorite staff of most people. Most people believe, it's the strongest of all when it comes to damage. This is almost true, but not at all.
Fire and frost staves share the same damage values. The advantage of fire is, that it can cause DoT's, dealing extra damage. You will deal extra damage against most animals, daedric enemies have fire resistance.

Light attack: 178
Light attack crit: 267
Heavy attack: 394
Heavy attack crit: 591
Impulse damage: 254

The problem is, that many people are playing Dunmer (especially in the Ebonheart-pact) they have fire resistance and quiet a lot people enchant their jewelry with fire resistance. There are almost more vampires than normal players and they have a fire weakness, but most vampires use 2 golden fire resistance enchantments. So you will probably never taste the full potential of the fire staff.

Frost staff: Pure PvP-Staff in my opinion. The snare effect is celestial and nobody uses frost resistance, yet Nords do have it and they are pretty popular. The staff shares the same problem with any other snare in the game: Their projectile flies soooo slow and it's so easy to block it. Enemy blocks= no snare, and the snare is why you take the staff, not the damage. You will deal extra damage against daedric enemies, but not against undead like skeletons and zombies. So it's also a good choice in some dungeons.

Light attack: 178
Light attack crit: 267
Heavy attack: 394
Heavy attack crit: 591
Impulse damage: 254

Shock staff: Pretty much the reason, why I decided to make this thread. Shock staves are a big topic and nobody really wants to use them. Because shock heavy attacks simply suck. The damage of shock heavy attacks is only a bit higher than the restoration heavy and its crit values are horrible, as only the final projectile and not the channel can cause critical damage. The channel itself (without the final projectile) can penetrate Dragonknight reflective scale. But the channel is much weaker than the restoration staff channel and is no valid choice.

But the shock staff shines when it comes to light attacks and abilities. Believe me when I say, that the attack speed of shock staves is faster than the fire staff and the shock staff always dealt around 20-30 more damage during my tests. Also attacks like Impuls deal more damage than the fire version (flatt damage). Fire Impuls will cause DoT's, so the damage of the fire Impuls will still be a bit higher at the end, but shock attacks lower the enemies damage done by 11% and this is a good trade in my opinion, as it also affects EVERY boss.

Light attack:187
Light attack crit:281
Heavy attack: 375
Heavy attack crit: 435
Impulse damage: 268

As you can see, the heavy attack damage is horrible, especially when we compare the crit damage. But the light attack damage, together with the higher attack speed of the shock staff, makes it the superior choice, when you plan a light attack build.

Unfortunately, light attacks don't seem to cause a shock effect. I've tested it with shock enchantments as well, but it doesn't seem to proc the damage mitigation, at least not on bosses. That's why a fire glyph is highly recommended for shock staves, as it always procs a small Dot.

Most people in PvP have unpenetrable traits on their armor nowadays, that's why crit builds become more and more inferior and this is the biggest strenght of the fire staff. I recommend to use the shock staff with balanced trait, to increase the light attack speed by 12%. Shock staves are the best staves for light attack waving (a quick light attack before you use any ability)

It's hard to find a use for the heavy attack of the shock staff. Full destro heavy attacks seem to restore 10% Magicka since the last update. If you use elemental drain on an enemy, you will restore Magicka, every time you deal elemental damage (Overload light and heavy attacks don't count! So stupid). The shock channel hits 4 times, so you can pretty much restore 100 Magicka with a single heavy attack + 10% and it does probably restore a bit more than a resto heavy attack and it deals more damage and has the chance to deal at least a bit critical damage.

That's it I hope, I was able to point out the benefits and disadvantages of the single staves. It's clear, that the shock staff still needs a small buff when it comes to passive skills. Nobody wants shock heavy attacks to deal 10% splash damage. The heavy attacks are bad anyway and 10% of that is not worth it. So maybe there are some tweaks needed, to improve that staff.

May Auri-El bless you and may Magnus fill you with Magicka.