I think starting with junior member will be kind of low, one person can just struggle to rank one of his account to member rank which after getting to member rank, he will start giving his alt accounts 1 merit which automatically his alt accounts are already in junior member, but if managers set standard to be member rank and above, it will be difficult for a bounty hunter to rank all his account to member rank, if you receive 10 merits, you will be able to send only 5 merits, so even if he will be sharing merits among his alt accounts it won't be easy, and he will be exposed easily if the alts account are not making quality posts and they keep on receiving merit from the same user.
Just assume a user with 5 alts accounts was caught and given negative trust, am sure it will really affect the user and he won't just create another multiple accounts because he knows even if he create them it won't be easy to rank up to member rank, so the user will just create one and focus on it, which some people wont even be able to rank 1 account up to member rank so they will have to give up.