The Darkreach is cool, but it's also... kinda boring? If you've escalated to nukes, than most of the ground units on the map are about to be wiped out, and if you can afford $225M for the bomber, you can probably afford ballistic missiles and don't need to waste times with gravity bombs. Piledrivers can hit one corner of the map from the opposite corner, and Tuskos have a 70+ km range. You just take off, point in direction of enemy, go full israel, and land. No real risk.