New to the game, fucked up my crew I think.

WoT forums seem to be down so I have to post here. I have played a fair bit of WoWs and do relatively well (55-56% WR), and went over to WoT to try things out.

Did the tutorial, where you get a 100% crew and it sort of forces you to take Sixth Sense. I did that, and also took concealment, which was a mistake because the russian line I choose goes into heavy tanks. I'm now at the T-28, a tier 4 medium.

I took the crew from my previous tank and retrained it (some for silver, some for free as I didn't have a lot of money after buying it). However because I messed up earlier and took concealment, I reset their skills in order to pick something more suitable for medium/heavy tanks further down the line. This has led me to a situation where I am missing Sixth Sense, and it's extremely brutal. In WoWs I mostly play cruisers, and knowing if you're detected or not is absolutely vital. In the second match with my T-28 I got one shot by artillery, 100% to 0% hp.

I thought it would retrain after a few matches, but Sixth Sense is increasing VERY slowly. It has gone from 78% to 81% over several matches. What are my best options here? Pretty lame system, this skill/perk seems to mandatory especially for new players, yet messing up like I did and being forced to pay gold to retain it when you progress through tiers seem like it's purposely made that way by design.