There’s another IW thread elsewhere in the forums, so I’ll copy/paste my comment from there:
As one of the lucky (?) few people who has and uses a Championed Invisible Woman, I agree that she could be better. Her green is expensive for what it does…especially since you either need her blue first, or to trigger her green twice.
I generally use her in PvE with Elektra and Hood. The two ladies tank for Hood (chivalry truly is dead! 
IW’s Invisibility almost always targets Hood. Hood’s main use is to steal AP often enough so that her expensive abilities can be cast a bit sooner than usual. I’ll fully admit that the AI has no clue about which tiles to lock down or when to use Elektra’s abilities, so this team is terrible in PvP…which is why you hardly ever see either of them in PvP events.
If you build IW at 5/3/5, you can control exactly what tiles get blown up when you trigger her green. While at 5/3/5 you can’t lock up countdown tiles, just put one of your Force Bubbles next to the Countdown tile you want to blow up, and then trigger the green. If there is one tile you absolutely, positively want destroyed, and your build randomly leaves a tile up, then put two force bubbles on opposite sides of the tile. Likewise, if there’s a tile you absolutely want to protect (a big attack/strike for YOUR team, for instance) you can lock that one up, so it stays around until after you blow the Force Fields. Sure, it might die to cascades, but you can’t really do much about that.
As with everyone else that uses a blue, green or red power, 3-star Iron Man works well as a battery for her. You don’t get her Grant Invisibility if you use the yellow for Recharge, but getting the rest of her abilities off that much earlier are generally worth it.
Edit - Forgot to add my tweak! If you want to get rid of the randomness, having the green blow up all of the locked tiles would be good. Conversely, you could make that ability both create and blow up the bubbles. If you do that, change the blue to do a stun, encasing the target in a Force Field. At lower levels, stun the target for 1/2/3 turns. At Levels 4 and 5, stun the entire team for 1 and 2 turns respectively.