Time Bomb is a conceptually flawed power. Teams don’t wait for the countdown, they jump right in. And blasters already have their top-tier nukes from the primary sets at that level. Time Bomb is just going to be picking off stragglers or damaging bosses, unless you’re solo or way ahead of the team.
I’d rather see them replace Time Bomb with a utility power, and improve Trip Mine instead.
They should make it a 30% damage buff instead.
It’s nice that they’re trying to improve Devices, but the set’s main problem is the lack of a damage booster like Build Up. Just tackle the problem head-on instead of trying to dance around it.