Alternative solution: Let every bitcointalk forum member with a rank higher than "Member" provide one airdrop address, and then "airdrop" 10 BTX to that address. (We will anyway not get more than 1000 user by this forum, so the airdrop should be smaller but fairer) This way you can more or less assure a fair distribution without concentration to whales.
Edit: The criteria could also be, that only an address with atleast 1 BTX coin inside is eligible for the airdrop, thus you can be sure that the person contributed to the coin either by
- Mining
- Claiming
- Marketbuy
I think that is a rather awful solution. You are just excluding newbies for no reason whatsoever, just because they are what not active on a forum? That is so arbitrary. But hey atleast you are trying, thats a postive here. I personally think the 2.5% is a great solution as it dissuades you from wanting to make multiple accounts, and only gives out a little bit of BTX (so only loyal people will play). It may not be perfect but it is certainly better than being able to spilt multiple accounts and get 10 BTX per wallet address. Lets see how this one goes!