I would advocate the method of moving to a fresh blockchain with coin redistribution through a trusted exchange partner.
I don't see a need for this? Other coins have transitioned over to POS without having to do this. Why would we want to go through that messy process?
POS is a viable option
if and only if 300+ clients are willing to go online
ie what coin has done this and successfully
Potcoin recently went POSv2 somewhat successfully. Actually it was kinda a mess because they forgot(?) to include
all the POSv2 code into the client before the switch (can't imagine!) and did not have a testnet to try out the changes but in the end they are now full POS.
There really does not need to be that many clients online to keep the blockchain going in POS (as I have seen with potcoin). One wallet can have multiple addresses or...have a low or user selectable (ideal?) nStakeCombineThreshold amount.
...but yes, having enough wallets/addresses staking is important and with the low level of interest in GLC I can see that being an issue.