That's why say virgin blocks mined in China, have more value than btc that's been tumbled online, virgin addresses never used private-keys are more valuable.
The latter is not true. As for the former, people won't buy Bitcoins that are taint free, that is just impractical. If exchanges cannot accept that the coins that they have will have some degree of taint, then they wouldn't be able to operate at all.
The problem here is the exchanges, so all 'mixed' coins are now tainted and un-usable; The solution here is to use lots of different exchanges worldwide, and find one that will except your tainted btc's, but I'm assuming most likely that if your btc comes from exchange 'russia', that coinbase will also call that tainted.
People like to deny problems, but the problem is the exchanges, and they're all being policed.
Has there been any exchanges that blocked your deposit specifically because of taint arising from it being mixed with tainted coins? All that I know is that they do not accept mixers or coins directly from restricted activities; gambling sites for example.
Another problem is depositing, I noticed the other day that transferwise will not send your money to bitstamp, I mean hell, its your money. So not only do the exchanges not accept your btc, but 'banks' will not let you buy clean btc from exchanges, so what's a mother to do?
That is a problem with your service, not with Bitcoin. You should probably talk to them about it.
Lot's of people use coinjoin ( modern replacement for banned mixing ), to combine change, but if the exchanges flag an address that's every been mixed then your btc is rejected, so then you go back to localbitcoins, and find a guy who pay's you 50% on the BTC, the new may or not be clean.
Exchanges flags coins that comes directly from a mixer but they do not specifically check for any degree of taint. Coins from an exchange is not exactly taint free either, Localbitcoins functions on a similar way like an exchange with their deposit/withdrawal system. I'm not sure how people get so much discount on LocalBitcoins, I've never seen it before unless they're outright scamming.
Look, if the concept of taint bothers you that much, then Bitcoin is probably not for you. I'll repeat this again; Taint does not exist on a protocol level. If you're supporting businesses that classifies any sort of privacy preserving activities as something that is against their ToS, then you probably would want to avoid them; they will probably collect more information about you. Most of the Bitcoins today are tainted, refusing to accept any taint Bitcoin will net you no business at all and your competitors would surely thank you for giving them your customers.