Nice poll!
2. For a Legendary member, receiving Merit should have a restriction or (may be just) don't apply Merit for them
I believe Theymos has ruled out preventing Legendary members from receiving merits. So my suggestion is to make legendaries receive 1 sMerit for every merit. It may allow some abuse of the system but it would put their accounts on the line and I don't think that would be a wise move of a Legendary member.
Anyway it's not actually a "hole" in the system. Lets say 10% of merits are gone to Legendary members every month. Increase merit generation by sources by 10%, problem solved! So it doesn't actually need a specific solution.