I just read this post and did not follow the whole discussion, but I want to point out the following:
If a character can be created at the levels 1,5,11,17 (which I wholeheartedly support) and downleveling is allowed (which is also good in and of itself) a character of any level 1-17 can be created.
Is that a bug or is it a feature?
Proposed fix: Do not allow downleveling to a lower tier
And on the topic of downleveling - would you need to give back magic items?