After reading the proposed abilities for power creeps, I found them to be extraordinary as well. Abilities like "Kill" and "DISABLE_TOWER" will have drastic effects on sieges giving up much of the defender's advantage in the existing game design. I'm finding it stressful to imagine making a power creep defense that is "safe" from other power creeps and newer players are pretty overwhelmed going up against boosted creeps as it is, power creeps + boosted creeps would be more or less unstoppable. With so many abilities, it'll be hard to account for and test each one when building an active creep defense.
Due to the range on the kill ability, The only way a non-power player can stay safe it is to build a base that is entirely ramparted which can lead to base layout conformity. I'd like to see more balance with power creeps and more ways of countering them without power by spending high amounts of energy, cpu, spawn time, etc.