I usually use the Clipsos FO when I need a good and safe button-pusher, though I find myself using her less frequently since the introduction of the Draal. I could also see myself bringing in the Minelayer option for disruptive purposes or the BSG option as a "living mine" in a place were I suspect a link team to cross. I am struggling with the Igao, too, though she can be pretty strong. I guess she's just a unit that is bound to performing inconsistently. She mainly lacks Infiltration (+6) to be great. The unit I include in almost all of my lists, however, is Jaan Staar. He's decent at everything, though not the best at anything. A jack of all trades, if you will. If I can, I will hold him in reserve together with a Kaeltar to at least have the option of deploying him with a mate and/or bomb. If you're willing to invest the orders, you can then place a mine around a corner and peek the corner in a subsequent order to give your target(s) nothing but bad choices. Whatever your opponent does, you'll have a good answer to it: Shooting, moving into CC, Pheroware tactics, shotgun templates. One thing to be careful about, however, is that Jaan struggles against the heavy hitters of an army (as he should). You'll be much better off attacking cheerleaders than the quarterback. Another thing to look out for is his deployment. If you deploy him too aggressively, he can fall rather quickly without accomplishing much. I know it's tempting to place him right at 36" but sometimes it's worth investing an order or two to get him in position post deployment.
Jaan Star deployed with a Simbiobomb after landing a mine is like, muahahhahaa, what you will do now, reset or dodge? LAWL!