The discussion section sounds like a solid idea. As for making LW less intimidating, I'd rank it as the grace period > doing nothing > "karma coward", though I think users should be able to exit the grace period earlier by choice, and also possibly the score of comments on users in the grace period should be hidden (not just kept from affecting the total karma).

Seeing your comments plummet in score might be demoralizing, even if it doesn't affect your total score.