Yes.  There is a second reason for not reusing addresses, and it is to improve privacy.  If you are receiving funds from different sources at the same address you still defeat that element.

It should be pointed out that 128 bit security is still beyond brute force for both current and future classical computing.  The main reason for not exposing the PubKey is if to protect it in case the strength of that key is ever reduced in the future.  This could be due to quantum computing making it possible to implement Shor's algorithm against the key, or ECDSA being weakened through cryptanalysis.  In both instances the effective security of the key will be reduced and known keys could be attacked without warning.

So to be safe... when spending... always create a transaction that spends any unused part to one or more of your other Bitcoin addresses  (or new addresses) that have never spent anything.

And when receiving funds from someone, always receive them at a newly generated address, if possible.

Using these rules would achieve greater degrees of security and privacy than if you did allow yourself to reuse addresses.

Wait now I'm confused.  Are you talking about output to a change address? I thought the change address would be safe because we are not sending from it.

Outputs that are received at a Bitcoin address are individually spent in their entirety. If you are using a wallet with coin control you have the ability to choose which outputs are spent in a transaction, and can therefore make sure that all outputs received at a particular address are spent together in a single transaction. If you are not using coin control, then it is possible that some outputs will be spent separately from others that were received at the same address.

Bitcoin doesn't distinguish between change addresses and receiving addresses. At the protocol level, it's all the same.

Interesting, reusing address analogous to creating history for credit or consumer worthiness.  A mulling point.

I think you misunderstand. If your public key is known then the security of your address is reduced.   Today assuming the wallet implementation is proper it is reduced by 160 bit to 128 bit security.  It is the public knowledge of the PubKey which reduces the security of the funds.  So public knowledge of the PubKey IS a security not just privacy issue.

Can a known PubKey lead to a loss of funds?  In most cases in may not but
* if Quantum Computing ever advances to a point where it is economical to break a 256 bit PubKey your funds could be stolen.
* if cryptanalysis advances to a point where it becomes possible to brute force a 256 bit PubKey your funds could be stolen.
* if your wallet implementation (or underlying library and/or OS) through deliberate intent or negligence ruses the same k value for the same PubKey your funds could be stolen.

There is no way to quantity the risk of the the first two factors however if it happens and you have funds stored in a know pubkey it will be too late.   The third scenario has already happened multiple times (android OS and bitcon.js).

The hash of the pubkey is a secondary line of defense.  It is like asking why can't I clean a firearm while it is loaded and the safety off.  In theory if you do everything right you could accomplish that without incident but taking that risk serves no purpose and if it doesn't end badly for you, if enough people try it, it will end badly for someone.

Any Localbitcoin Sellers on here?

Reading this thread made me a bit worried about the auto-generated blockchain wallet attached to our accounts.

Apparently we can change them (+still have access to previous?) but thought it's pretty damn secure at any rate. What do you guys reckon?

Blockchain.info ?  That's an online wallet.  The main risks there are
some hacker steals your password (please set up 2FA!) or
the site itself is hacked or internally compromised.  (Goxxed).

Although I trust Blockchain (Andreas Antonopolous is their chief of security)
infinitely more than Mark Karpeles and Gox, its still an online wallet
and it could happen.

Those things are probably more likely to happen than
you losing your coins because of address re-use.

He said cryptoanalysis and quantum computing, not ordinary brute-forcing, but you're right. 

On a side note, will the sun really "explode"  or just burn out?

No you can't.


Which has nothing to do with the points you "quantified".