I've been mostly on a Minecraft binge, lately, with some EVE Online on the side, so I haven't been playing Cardalaxy much, recently.
As of the time of this writing, the current version of Cardalaxy is Alpha 0.5.2.
In the 2 rounds of Cardalaxy I've played recently, it feels like the Defense and Wellness tracks are in healthy places. Neither system feels like "YOU ABSOLUTELY MUST DEAL WITH THIS TO THE EXCLUSION OF ALL ELSE!" In addition, it's a nice touch to be able to get a small number of Production points from destroying Local Threats; the Tier 2 buildings "Launch Facility" (2 Production 1 Exploration) and "Modular Farm" (3 Production 2 Wellness) aren't absolute must-haves. (It used to be that if I didn't see "Launch Facility" or "Modular Farm" early in the Technology Tree, then I would quit the game and start over.)
I would need to put a few more hours into playing to be sure, but overall, I think the game is in a good place, metaphorically speaking.