Review for those with no $ to spend.

Obviously, WoT is another one of those games where the players who are able & willing to spend money succeed the most. Those (like me) who cant afford to buy their way to victory, must work towards being strong supporting figures within the alliances they join. Some game set ups allow the players who are not big spenders to get as much out of their involvement as possible, but WoT is not one of them.
Although WoT proceeds like other MMOGs early on, on each world within the game you reach the point where dragons become available. Dragons cost a lot of gems to buy & gems cost $$. Yeah, WoT lets you get gems for free, in small amounts - and if you dont spend any of those gems in the weeks leading up to the dragons, you MIGHT have enough to buy one. But unless other, more experienced players let you know this, you wont be hanging onto the gems.
(Thats another big flaw in WoT: the rules information that players can access is VERY limited.)
If you cannot get a dragon, the game is, essentially, over for you. Dragons greatly increase the power of players armies and allow the training of special troops to attack with them. Also, most of the game events begin to offer rewards that are only usable by the players who have dragons. At this point, players without dragons become nothing more than targets.

Cynran about War of Thrones – Dragons Knights Story & Kingdoms on Fire