None of the ways are worth it, period. Consider that Mentor spirit typically gets you .5 PP.
You probably shouldn't have a Quality that costs 20 Karma. It's simply too big a chunk of things at chargen, and 40 pts is stupid after chargen. (and then they hedge this, but only sorta, with this retcon at GM discretion thingie....wut?) They probably should be a quality, period, and 20 is too much, period. Also, having the benefit be so variable (1/2 of one level, which varies imensely) is absolutely crazy.
The fact an adept has to pay for Way to get certain metamagics, enhancements is also stupid....mages just pick one they want to grab per initiation. What's wrong with that for adepts?
The Way system is so wrong, I can't think of anything right about it.
Drain codes and other spell weirdness probably should have been a priority, becuase they were jsut the most obvious fix. But if you're just saving adept power re-balancing and Way errata for another pass......please tell us that. Cuz otherwise I'm worried you think it's just fine the way it is.