You don't need 10 factors for a coin/Bitcoin be decentralized. The creator being known or not doesn't even matter, for example.
What you need is:
1. Decentralized database/ledger for recording the transactions; for example, a blockchain.
2. The nodes being as many as possible and geographically spread as good as possible.
3. No central authority that distribute the coins.
4. This may not be necessary, but it surely helps, is to have the miners / pools also spread or geographically.
5. Something useful is also the way the changes in the code/logic (new clients/nodes) has to be accepted by the majority.