WOT takes a while to earn any good tanks. I have the Tiger I, Panther II, Lowe, Wespe and one more arty. Basically Im on the treadmill now as it takes a bazillion points to earn the King Tiger which is next on my list.
My tanks are maxed out and the crews are pretty well trained by now but theres way more to go.
Now that there are some crazy high power tanks above my level 9 tanks its very hard to take them out and win. The 88 on the Tiger was a great gun in reality but in the game its just OK. The Panther is awesome in some respects but weak in armor. Reload times are good and the gun is too. Great for scouting and run and gun but not good to go head to head.
Arty is fun but reload times are horrible so it takes patience and timing.
I bought the Loewe because at the time it was one of the big boys now its surpased by higher level tanks. Its great for just earning credits and experience and thats why I bought it.

Tunisian Tiger