Stats Overview

[CubedOobleck]

http://warframe.wikia.com/wiki/Warframes_Compare
The link sends to the warframe wiki page with all the stats that define each warframe, granted powers are what matter the most I would still like to share my point of view on these stats and how they balance out.
  
Shield capacity is arguably the most important stat in the game, it's what you always keep your eyes on and defines how long you can take damage (and deal it by consequence) before you need to take cover or resort to powers for help. Redirection is always worth using to a certain degree.
 Shield recharge rate is probably the least important stat as it's very similar among the various warframes. On the other hand you can benefit from fast deflection with any warframe. 
Health is basically just a buffer you need while you run for cover if enemies ever get past your shields and can be ignored unless you are facing a Toxic or enemies far beyond your level. The importance of health is further reduced by the sentinel's ability to replenish shields. Vitality is hardly worth using due to the current passive level increase. 
Armor essentially increases your health without increasing how many health orbs you need to heal up. Low armored warframes won't benefit from Steel Fiber and highly armored ones don't really need it. 
Sprint speed is among the more important stats, you can live with it if it's low, but mobility is undeniably a key factor in this game and defines a lot about how you use your warframe. Depending on your gameplay style it is worth using Rush and/or a stamina mod.
Power can be very important depending on how much you spam skills. Energy orbs are abundant but if you like to stock up Flow can be useful, but it is not a necessity with the current passive level increase.
 
In all this I find that DE tries to use health and armor as a method of balancing on par with shields and speed when in actual gameplay they don't matter nearly as much. This leads to the current tank debate: is all that extra health and armor worth the loss in speed? I think not, in this game you are a tank when you have the best shield, which is why I would argue that Mag and Volt are basically on par with Rhino and Frost. Mag and Volt should not have more than 125 shields while Rhino and Frost should have at least 175 shield, as well as better recharge rate, Saryn should also have 125-150 shield.
Ash is possibly the best warframe when it comes to sheer stats with nothing below average (excalibur as average) but more speed, health and armor; this is somewhat strange as he is supposed to be a stealthy character which notably aren't very resistant.
Ember also catches my attention with 35 recharge rate: Banshee, Nyx and Trinity are identical in every other stat, but their recharge rate doesn't go beyond 20-22.5.

 

Although the effect of the alternative helmets is very slight some of them are badly balanced nonetheless. Ideally the trade off should be slightly positive or at least equal, but never bad. Also, my ocd tingles at the fact that some helms have a flat increase when the most are percentages, but not just that, these flat increases were decided before warframes had a passive stat boost from leveling up and are unbalanced.
Scorpion (Ash) +25% stamina -5% power efficiency; power efficiency loss is somewhat important, but stamina gain is almost useless, at the very least it should increase stamina recharge rate.
Reverb (Banshee) +10% energy -5% health; somewhat positive tradeoff.
Phoenix (Ember) +37 energy -5% shield; I don't understand why they bothered with a flat increase of energy rather than a percentage, the tradeoff is so-so.
Avalon (Excalibur) +25 shields -5% health; if you don't mod your health, the trade off is positive with a loss of only 15 health.
Aurora (Frost) +33% armor -5% health; the tradeoff is slightly positive.
Essence (Loki) +15% power efficiency -?% armor; the tradeoff is positive, the base armor is so low that any percentage won't make much difference while Loki's survivability relies on his powers.
Coil (Mag) +30% power reach -5% shields; the extra reach is huge (like a maxed out mod when the rest of the stats are equal or less than a unranked mod), compared to the rest this helm may even need a nerf.
Menticide (Nyx) +25% stamina -5% shields; definitely a bad tradeoff, shields are important whereas stamina isn't, sprint speed or power efficiency should be increased instead.
Thrak (Rhino) +25 health -?% sprint speed; 25 health is so negligible, while speed is such an important factor of this game and rhino is already so slow this tradeoff is like salt in a wound, but the issue is that no stat is worth reducing for +25 health, at the very least increase the shield for the speed loss.
Hemlock (Saryn) +15% sprint speed -5% health; positive tradeoff.
Aura (Trinity) +15% power duration -5% health; positive tradeoff, although technically to gain the best from the link + energy vampire combo (which I disapprove of) it's best if the powers last less.
Esprit (Vauban) +10% energy -10% shields; somewhat negative because Vauban already has a vast pool of energy whereas shields are always important, perhaps should be -5% shields.
Storm (Volt) +?% power strength -?% stamina; should be positive.
 

Ash feedback - https://forums.warframe.com/index.php?/topic/17085-ash-feedback/
Banshee feedback - https://forums.warframe.com/index.php?/topic/46387-banshee-feedback/?p=469683
Frost feedback - https://forums.warframe.com/index.php?/topic/42221-frost-feedback/

Loki feedback - https://forums.warframe.com/index.php?/topic/64930-loki-feedback/

Nyx feedback - https://forums.warframe.com/index.php?/topic/37656-nyx-feedback/
Rhino feedback - https://forums.warframe.com/index.php?/topic/19790-rhino-feedback/

Saryn feedback - https://forums.warframe.com/index.php?/topic/63519-saryn-feedback/
Trinity feednack - https://forums.warframe.com/index.php?/topic/24289-trinity-feedback/

Vauban feedback - https://forums.warframe.com/index.php?/topic/68822-vauban-feedback/

Edited June 23, 2013 by CubedOobleck

[CubedOobleck]

Updated