The bottom line is that right now today, with no changes to anything, if you end up with coins bearing an interesting history, you take the risk of someone becoming interested in you.  You cannot prevent this risk.  You cannot mitigate it.  If you ditch the coins, you are still part of the chain, and you may get a knock on your door from people wondering how they came to you.

Widespread mixing, if and when it arrives, will hopefully muddy the trail of every transaction, maybe even to the point that most investigations become futile.