To be honest, it would be fair to give XRB holders exactly the amount they currently have on their adresses. BUT, then you would have the problem with the whales and also the problem that it makes rich people even richer. So you have to come up with another solution. Since it is very difficult to be fair, one would always have to compromise.

If I were felixando, I would probably do the following (just a suggestion):

Donators
I would hold back 15% for donators and pay them out in percentage of their donation. Here the respective course should be considered at the time of the donation. If we assume a total supply of, for example, 150 million stone, that would mean 22.5 million coins go to the donors. However, I would maintain the opportunity to donate until the coin is published. In this way, you can even later collect enough money for the development and/or your work. Otherwise, the procedure would actually be considered unfair, I think.

XRB Holders
I would distribute 55% to existing XRB holders, but I would only consider accounts that hold more than 1 XRB. That would be about 40,000 accounts. I would pay those accounts exactly the same amount, ie the maximum number of coins divided by 40,000. In this way, the holders who have little get as much as the holders, whom we call whales. Assuming a total supply of 150 million Stone, that would be 82.5 million coins for XRB-Holder or 2,062.5 Stone per account.

Thread-Poster
I would rather divide the 10% for Thread Poster and also think of possible bounties. For this reason, I would give the posters here a maximum of 5% and distribute this in equal parts among the people. That would be at least 7.5 million Stone for those who post here. Another 5% I would necessarily store for any possible upcoming bounties, which could later be awarded for additional work from the community (eg website, whitepaper, translations, moderators, graphics, Facebook and/or Twitter campaigns, YouTube videos, other material, etc.).

Dev-Fund
I would increase the development fund to 10%. For example, for the sake of fairness, 5% could be immediately released (about 7.5 million Stone), another 2.5% (about 3.75 million Stone) can be blocked for 3 years, and another 2.5% (approx 3.75 million Stone) for 6 years. In this way, the Dev (Team) and / or Felixando would have a sufficient fund of development and payment every 3 years.

Faucet
In this way (see above), you would be able to distribute a total of 90% of all coins to the community. Most of them would actually hold XRB, have donated, have participated in the thread and would possibly participate in the future. Felixando would have enough money to develop the project without worry by donations and the dev-fund. Because a secure future for the project is very important. With the remaining 10% (about 15 million Stone) of the coins, I would create a Captcha Faucet, which could also be used very well as a marketing tool.

BTC-Holders
I would completely cancel the BTC Airdrop for BTC Holder. Why should you necessarily participate in BTC Holder? On the one hand you have the problem with the whales and on the other hand there are a lot of (!) mainstream users who may not even know how to claim the new coins. That's why, sooner or later, many coins would be broke here.

But these are just my subjective ideas. Feel free to optimize

So, in short:

• 15% for Donators
• 55% for XRB Holders
• 5% for Thread-Poster
• 5% for possible Bounties
• 10% for Dev-Fund
• 10% for possible Faucet

PS.: Just by the way @felixando: Testnet, please? Fourth attempt

EDIT:
The total supply of 150 million Stone should be just a suggestion or an example to describe the shares better. How high the total supply really is, of course, is the decision of felixando. So please understand only as an example for the bill. Thank you