We can go with middle ground and do this : Bloatick Trap spawns a tunnel, which if let alone for 2/3 seconds, will spawn 3 bloaticks. We can decide whether the tunnel should be invincible and only act as further warning, or we can make it deniable.
That way it can retain it's lethality towards the unaware but is still less of a 'click here to delete units' power. How about that?
I think it making it invincible wouldn't be broken. We would end up with the same support power as before, except with the delay that makes the power less annoying.
If you make it deniable then it completely removes the ability to drop the bloaticks near the enemy army. You wouldn't be able to do something like drop Bloatick Tunnel in the enemy's escape path to do a pincer attack. which hurts the support power too much imo.