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For technical reasons (ability to control the fee token on the 2nd layer), I think the most likely way we will need to do it is make an airdrop of the L2 token on Hive holders that is strictly proportional to their Hive holdings.

For the short term, it could be okay. But for the long term Hive would profit much more if it would be the Main token.

Only for the reason social + smart contracts = Hive (token).

It is better for marketing, Users, and Investors IMO. The Sidechain that would offer this, would become the main sidechain for Hive in the long run.

20 different sidechain tokens are difficult and make everything too complex in a long run.

I think we will have at some point one smart contract chain, new tokens will build on it.
The best case it would use Hive.

Because after the Airdrop, new users need to buy another token, and hive would stay pretty much the same.

Only for the point of marketing would it be a big favor.

I don't like Hive engine because of the Tokenomics. It's not for every Hive user that holds hive and belive in hive. It has its own space and it's not fully connected. Otherwise, I had invested time and money in some ideas I have on it :)

I think Binance has done it smartly. Maybe it can be something for hive too. You are the technical expert :)