It should never allow you to reemplace a transaction, or to change outputs,
it should allow you to give more priority to a transaction that it's stuck on the limbo of 0 fee/smaller fee transactions.

Only replace the transaction if it's the same transaction with bigger fee. to the same outputs.

Any other thing is not bitcoin, btc is not reversible.
or you just killed satoshi dice.

But talking about improving you could also change the 10 min confirmation to 2 and slash the rewards 5 times.
then they will change to a 1or 2 confirmations .