I asked two questions which I later learned were apparently preposterous and got heavily downvoted and closed. I lost some of the 101 rep I started with and now I'm at 91. If I make my account die, I will be back at 101. I don't see any reason not to make my account die. Is killing my account to restore my rep to 101 bad?
That works, and if you do it once or twice, people probably wouldn't even notice.
If you do it repeatedly, that would be a different matter. Accounts which keep on asking poor questions are warned and eventually banned from asking further questions. Deleting and recreating accounts to avoid question bans (even if the system didn't warn you yet) is a definite no-go and can lead to suspensions.
If you're certain the questions are problematic and cannot be salvaged, it's better to delete the questions instead of your account. (This is possible because nobody posted a positively scoring answer yet.) That will restore (with a few minutes delay) the reputation you lost from the downvotes on them.