Technical Questions for Ethereum

[Neotopia]

I have a few technical questions, and hope someone can answer them.

I have done already my research, but some points are still unclear to me:
1.) Are projects like TenX (ERC20 token) running on the Ethereum Blockchain or on its own?
2.) Can any ERC20 token choose its own consensus model? PoW, PoS, etc.
3.) Why would one make a private blockchain? What are the reasons for this?
4.) Is it possible to replace one token with another? e.g. the blockchain technology must be radically changed?
5.) Is it advisable to store more than pure transaction data in the blockchain? For example, the number of victories of every national soccer team worldwide?

Thank you!

[relest]

1) Yes, it's ETH
2) No, it can't
3) There can be many reasons, one of them is the reduction of fee for transactions
4) No
5) No, it's too expensive to store big data in the blockchain

[Neotopia]

Thank you for your reply.

For 4.)
Do you know how it usually works with the Pre-Tokens? As far as I get it, this aren't real use tokens and therefore, they get migrated to the final ones. Another sample would be AntShare I guess. They converted into NEO. Is this just a rebranding or was the technology also changed?

For 5.)
Is there any sample known, where more than just transactions data are stored in the blockchain?

There is so little information about this two topics.