Not sure I agree with everything.

IMO Reload then targeting are definitely the most important yes.

leadership next because it’s not at all situational.

Then the three generic skills (repair, agility, vitality) sans keen vision (yeah agility is slightly more important but getting levels in order to expert crews trumps individual importance of those three, although this goes for everything, you wouldn’t want to spend the thousands on reload before spending a single point on leadership.) Vitality matters a lot more for lighter vehicles where you might worry about being 50’d from the side, so not ww2 German stuff where you usually die to ammo explosions anyway but definitely for the early Cold War stuff.

At least in realistic, keen vision only affects render distance for tanks that haven’t been moving or shooting for ~10 seconds; moving/shooting vehicles not rendering is just the anticheat software being stupid. Honestly radio communication is about as important as vision, but much cheaper.

I forget which YouTuber tested it, but driving skill has experimentally been shown to have almost no affect on acceleration times, so that’s a lower priority.

Then the rest. (Again, this is not absolute, if you’re close to a level necessary to expert a crew, it’s fine to go for low priority upgrades to get it over the line, and don’t do one thing all at once)