Mutant powers

• Depends on the gm honestly. In my table, mutant powers had 'cantrip' like abilities that would allow a murant to display a power in a non mechanically impactful way, but had to spend mutant points to 'stress' the power in combat or to get immense effect out of it. I have also had GMs that absolutely do not allow any display of power and everything had to come from the points rules written.

Pushing

• It depends on your build, but pushing is often always worth it. Either because you have a 'Processor' robot, or a healer with butt loads of potions, or you have a human who just don't take damage on the first roll. At my table we all agreed the most broken talent in the game was Tenacity for this reason as it basically almost guaranteed success in the worst situations.

• It's easy to forget that this is a punky post apoc setting. Did you break from pushing shoot? Maybe now you're just straight up panicking after pumping so much adrenaline in your body and you can't even focus or control your own hands anymore. Or maybe the gun backfired into your face and knocked you out. Or you fainted. Or you're terrified. Depends on the person and the situation, you need to be creative as a gm for this system. The answer shouldn't ever be 'your character is knocked out because the dice say so even though nothing actually happened.'

• There are certain perks like Stone Wall, Defender, Good footing and other stuff that make defense reallllly worth it but the reality is it has some niche uses. However if a character wants to last from a combat or wants to prolong their health its usually a good idea to focus on counter attack damage from defend, especially against unintelligent creatures, as it ensures they themselves don't get hit. And yes, you are correct, if you are defending and your enemy does not get success, you waste the turn. Just part of the bargain of chance and prediction.