I don't quite understand this proposal...
BitAssets are not created by "burning BTS", they are created by putting some amount of BTS to be a collateral for the created asset.
(And Bitshares isn't even burning BTS, it puts the BTS from fees to the reserve pool.)
But I like the idea of using BTS that network collects from fees to increase liquidity. Helikopterben's proposal was better, although would it create a problem by making a lot of orders on the exchange? That would use a lot of memory, especially when many of those orders would be there maybe forever. Would it be too much?