Starting it off I'm going to start with Crew Skills and go on specifically about the common ones that every crew member can use. Please note this will focus primarily on the first three or so crew skills, all skills and perks are useful at some point but certain ones I'd only get when my crew reaches 7 or so crew skills.
Repair
Value - ExtremeType - Accumulative Skill
If your crew has 0%, 0%, 50%, 100% then the effective repair would be 37.5%.
Description - The repair skill decreases the time it takes to fix destroyed modules.
Suggestion - All tank roles besides artillery should get this skill very quickly and your priority on getting it depends on your survivability when getting tracked.
Why Use It - In essence; survivability. When tracked you have two options, to repair it with a consumable or wait for it to come back. With a decent repair level you'll burn less repair kits on tracks so you can use them for more important things like ammo racks.
| With Repair | Without Repair | |
| Tracks | 3~ seconds | 10~ seconds |
| Gun | 7~ seconds | 15~ seconds |
| Turret | 7~ seconds | 15~ seconds |
The worst scenario to be in without the repair skill is getting tracked right before your gun rounds a corner meaning you can't shoot back. I personally do this every chance I get in my tanks and if I'm in a tank with a 7 second or faster reload (auto loaders and mediums mostly) I'll have at least a 50% chance of destroying them unless they burn a repair kit. If they had repair at 100% only very fast reload tanks like auto loaders can keep them permanently tracked.
Camouflage
Value - ExtremeType - Accumulative Skill
If your crew has 0%, 0%, 50%, 100% then the effective repair would be 37.5%.
Description - Improves your camouflage value decreasing the chance of being spotted.
Because of an increased camouflage value, enemy tanks need to get closer to detect your tank.
Suggestion - All tanks should eventually get 100% camouflage, Tank Destroyers / Lights / Mediums should get them very early on as it compliments their play styles while Heavies and Artillery would benefit from them later on as both of them should use objects for cover instead of view range as their primary form of protection.
Why Use It - Camouflage improves one of the core game mechanics of the games meta, view range. The time you are visible to the enemy tanks the more your survivability will go up, and in a lot of cases it is by a huge margin. It improves sniping from range, advancing on a position, and so many other scenarios that it is hard to appropriately explain why it is so useful. However in random battles where you have to rely on your own ability to spot tanks before you're spotted, this is a life saver.
Firefighter
Value - Very MinimalType - Accumulative Skill
If your crew has 0%, 0%, 50%, 100% then the effective repair would be 37.5%.
Description - Decreases damage and duration of fire damage.
Fire damages your tank over a set time and deals a percentage of your health with each hit.
Suggestion - Since fire extinguishers are very cheap and automatic ones can be bought for credits, compounded with the fact that you rarely see double fires makes this skill relatively useless. I'd pretty much only put it on tanks with 5+ crew skills due to lack of useful options.
Why Use It -After you've collected all the very useful crew skills you'll eventually reach a point where the options become mostly perks, at this point giving a crew member firefighter becomes a valid option. If it decreased the chance of being caught on fire then it may gain a better standing on those tanks with very weak engines and fuel tanks however in 99% of cases you are better off with an extinguisher, let alone the alternative crew skills you could be using.
Brothers in Arms
Value - DebateableType - Special Perk
Your entire crew must have it at 100% and after an upcoming patch none of the crew members can be injured or else the effect is removed.
Description - Increases crew effectiveness by 5%
This is a buff to crew training and in effect influences everything from rate of fire to turn speed, camouflage value to view range, however the effect is closer to 3% when translated to actual effectiveness.
Suggestion - Because the commander has to learn it 100% aswell and it offers such a low buff across the board I only recommend it for artillery until you have a multiple crew skill crew. Probably around 4 or 5 skills each.
Why Use It - In the beginning of my tanking carreer I believed that BIA was extremely valuable for my tanks, and on certain ones I still hold that notion. However as I have matured as a player I have noticed the impact of getting crew skills that enhanced role specific functions over a uniform buff. My tank destroyers live longer and get greater damage with camouflage as their first skill while my brawling heavies stay alive in a brawl longer when I don't have to burn a repair kit to fix their tracks when I need to dodge in and out of cover or angle my armor for a greater chance of bouncing shots.
In such tanks as artillery it is indeed useful as a first crew skill since you don't really need any other crew skill to preform your role well since your primary concern is with accuracy and reload rates which none of the other crew skills usefully influence as much. None of my recent crews minus my new artillery crew will have BIA until they have around 4 or 5 crew skills since the commander has so many important skills to learn that it is just not useful to waste a crew skill slot on it.
Conclusion
Repair - First or Second skill on almost any tank.Camouflage - First or Second skill on any tank.
Firefighter - Only get it when you run out of skills.
Brothers In Arms - Only useful early on for an artillery or a very select few tanks.
