There is no problem with you hosting the random-number-generation, because there are easy ways to make it transparent and fair. If you are uncomfortable, then there are plenty of trusted members around here that would help you out.
How To Play:
Pick one of the available Tickets from the table above. Post a reply with your pick + the txID of your transaction.
Once all Tickets are taken (and paid for) I will select 1 future mined blocks that will determine the winners.
The last character in the hash of that block will decide who has the winning Ticket.
This gives you 16-slots. ^
The following thread is an example of turning the same idea into a 64-slot raffle with 3-winners:
https://bitcointalk.org/index.php?topic=5129234You can expand it further if you have more participants. As long as you pick a future block, nobody will know the outcome and everyone can find out the winner simultaneously and live - without any middleman, interference or trust required.