Feel free to poke holes in this... I am the king of horrible ideas apparently.
A. User wants to buy BTS
B. The committee members publish the Bitcoin address, so delegates can monitor it using a Bitcoin blockchain data API (multiple ones in case of down time.)
C. A BTS user sends BTC to a multi-signature address setup by committee members.
D. A smart contract then "prints" BTS for the user using the current market value (via delegate feeds) worth of BTS whenever over 51% of the delegates agree someone has deposited money to the address. It would then be redeemable similar to PTS/AGS shares.
E. The user has BTS that he will likely not dump immediately, as he got no discount and paid the current market value.
F. The BTS token supply grows, but there is no immediate (or certain) downward pressure to the BTS value.
G. Downward pressure by the developers selling the coins for expenses happens on other chains, positively affecting BTS value by reducing downward pressure.
This could possibly be gamed with any coin other than Bitcoin, which is why I suggest we only allow Bitcoin deposits. The cryptocurrency used in this must have large enough liquidity so that it cannot be easily gamed. Maybe you could tie bridge services into this idea somehow since they already have the bridge part taken care of.