BTW- thanks all for the insight & analysis so far!
Tell me more.
I ask because I can see the obvious benefits of the 2 AoE attacks. They'll be better crowd control than the power the Wizard is likely to take- he's cold themed, so I'm betting he'll get Bigby's Icy Grasp*- and most of my other powers are single target, thus expanding my tactical flexibility.
* though it's possible he'd take Fireball- a historical favorite of his- if I took Crackling Fire.
FoG let me teach a couple of flying enemies that being knocked prone, then being locked down by the Defender is not fun, over the levels. I've used it to keep Brutes out of the fight, for a round. One BBEG learnt that it isn't fun to have to choose between action economy, and hit penalties.
Also remember that the effect persists and save ends. I think that the best I got out of it, was 4 rounds.
Did you ever have a problem with monster making the acrobatics checks to avoid falling prone? That's the issue for me: The attack needs to hit, then you need to hope they fail the check, then you need to hope they fail the save for it to continue. That just seems like its stacked against the poor Starlock.