I did the same thing, with Litecoin, when I first started! Freaked me out thinking that all my coins got stolen! Now I always reuse an existing address for change.
There is a it's a good idea to use fresh change addresses.
Although, we won't have to worry about the problem for years to come.
Once an address has been /sent from/ its public key is visible on the network.
Eventually, years from now, a quantum computer may be able to compute the private key of that address given it's public key.
But, since addresses are /hashes of/ public keys, un-sent-from addresses are not susceptible to this particular attack.
I've proposed for some time now a feature to be able to add a static change address to the config file. Obviously this has potential anonymity issues, but on the other side of the scope it brings great benefits for many different types of operations out there. Be it at a private or corporate level.
The proper way to manage this is with deterministic address chains. (BIP32/BIP44)
Best of both worlds. Fresh addresses and absolute certainty your funds lie within your chain/your control.
Agreed. But how do I implement this with the QT ? Is this currently possible, or a future possible feature ?