I'm still on my 2nd game (*gasp*) and I'm actually having a blast with it. I look forward to playing it and think of it when I'm working or driving (the Beyond Earth music I play in my car helps with that too, haha).
I thought I would be a Supremacy guy, and tried to go that route while roleplaying a little bit as the ARC my very first game. But, I lacked the Firaxite around my territory and other things weren't going so great.
That game was mainly exploratory, so I cut it sooner before finishing it and started up a new one. This time, however, I let the land dictate which affinity I'd go for.
Floatstone... floatstone everywhere... "Damnit!", I thought. Out of the affinities, Purity looked the least interesting to me and I thought the units looked dumpy in their dirty yellow/brown trash color and big, clunky looking machines with too many things on them compared to the streamlined and sexy Harmony and Supremacy ones.
Man, was I wrong! Once I started building an army of battlesuits, I felt really epic. I just love the centurion-inspired helmets, their hulking armor, and most importantly those red capes... the capes are so very cool. But, things got even better once I got my first levitating unit, the lev tank. It's a lot of fun traveling alongside my navy, ready to blast things away, or taking shortcuts through things like canyons. And the lev destroyer is just a big metal heap of beastliness.
Two nights ago, I was delightfully surprised by another thing. I didn't know that the final versions of all my vehicles gain the hover ability too! I'm at war right now with someone on another continent, (who has been annoying me and condemning me lately) and I'm just speeding across the ocean and cruising all over his continent and coasts while I wipe him off the map and purify "my" planet further.