Yeah as King Rich said stick with the German arty as you need Bombardier anyway.
As I said before when you use XP to buy certain upgrades or guns it makes them free to research on other tanks. I researched the big gun package for my Tier 9 arty for 0XP because I'd already acquired it for the Tier 8. I'm now just working towards unlocking the Tier X.
Basically at first the XP requirements seem harsh but as you unlock things, other things reduce in cost so it gets easier.
I was working towards Tier X anyway as I always suspected this achievement would come around. I'd probably already be there but I seriously needed a break from the game
On the plus side, anyone can get this achievement as it's just a grind so I'm okay with it. I'll also try to hunt for light tanks from now on in an effort to combine that achievement.
As you say though, the game has forced you to go off in several directions. The Soviet heavies really took away a lot of the Silver I had and now I'm trying to earn some more to buy those Shermans from the American line after having just forked out 3.6million silver for the Tier 9 arty and a further 360,000 silver for the big gun!!!
The way I have been working is that anything I buy, I get it to Elite status before selling it as I have been trying to unlock as much as possible. The only mistake I made was selling my Tier VII British before I'd really even used it and I've never had the silver to re-buy it to finish it.
As you commented earlier, this game and many other free games are geared towards paying to fast track your way through. With achievements like Bombardier and one or two others you may as well just go it the hard way and hope you pick up the luck based ones on the way.
Chin up man, as said above you're a good way through the game, the ratios are pretty good, the amount of completionists will be low and it will make you feel good when you get there. Rich has earned many medals over and over and I have two Bombardiers and two Pascuccis under my belt which I never thought I'd get. Keep those tracks rolling buddy!!!!
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