Another issue is that YAC needs protection from 51% PoW attacks and with PoS trust=PoW trust we would loose such.

Bitcoin has a unique hash-algorithm so that the bitcoincommunity with their hardware can compute far more efficient than the rest of the world. This makes it extreme hard to attack it with standard computers. Cryptos like LTC are mined with a lot of GPU's which are also not that common.

A CPU on YAC has around the same hash/s as a GPU so a botnet could easily rape us without 51%protection from PoS.
This makes me belive that PoS trust=PoW trust isn't possible without some sort of checkpoints. Somehow I think we need some sort of CentralCheckpointing...

What do you guys think about the following:
A PoS blocks trust is limited to a singe PoWs unless it get's confirmed by CentralAuthority CA in the next block. Such CA only needs to send a txt to the owner of the previous block. This would limit the power of CA to reverse just a few blocks and could only be done once. Everyone that was online would notice such by having 2 different forks which both have a confirmed PoS block in it. Miners are usually always on.

In order to get rid of the Central thing we could allow everyone to send such txts for a fee. Only the authority with the biggest balance get`s accepted and will get a small % reward later on. A minimun for becoming a CA should prevent someone to fake beeing a legit member of our community and a thief would rather steal the whole adress.

If (or better since) this isn't enough damage for someone that abuses his power we could also go where it hurts. I don't see any problem if all miners would agree to never ever accept a txt from an adress that was used to scam the whole community by this. Since freezing funds would also be nessasary to have more than just one guy getting all the rewards this wouldn't go much further. Opening a box we should never even touch... Baaaaad.

EDIT:
Reward could be randomly given to one of the 10 biggest CA-candidates that participated based on howmuch coins they have. Since sending a txt from a wallet has to send the spare change to a new adress we shouldn't go by biggest balance, we should go by biggest output.

A cooldownperiod of [n(no of candidates)+5] PoS-blocks would allow all candidates to participate and reduce the damage a single wallet can do.

EDIT: Requires also no 2 PoS blocks touching.