If you enjoy Xcom, youll get a similar feel from this game. Its a pretty good title, with a nice sized skill tree for several different classes, which branch into two more specialized roles. Additionally, theres a sizeable research tree and most components can be purchased via in game credits if you wish to speed along your progression.
You also have a base management section, which handles like a mix of Xcoms base management, and a free to play city builder game, where certain structures run down timers before spawning resources (credits typically). Base buildings can also be upgraded for improved effect etc.
As for the free to play aspects, most can be easily circumvented. Tokens to speed things up (normally costing paid currency) can be purchased (very cheaply, I should add) for in game cash, and you can frequently find more in missions.
The only Microtransactions Ive noted are for credits, and for a separate currency related to PvP (which is likely earned similarly to credits, and thus optional).
All in All, I heartily recommend that you give the game a try if youre hunting for another turn-based title similar to Xcom.