Pay higher transaction fee.
Problem solved.
If the transaction fees get high enough, then less people will create less transactions (because they don't want to pay the fees). That will reduce the number of unconfirmed transactions. Then fees can get cheaper.
Problem solved.
And this will eventually result in Bitcoin Cash( Or any other altcoin with bigger blocks & faster blocktimes) overtaking bitcoin.
Why would anyone want to use a currency where you should pay 30$ to make a 50$ transaction that will go through in a reasonable amount of time?
You don't solve the problem by paying higher fees, you simply prolong it.. Until you either need to pay even higher fees.. (Or until bitcoin is worthless and has no usecase anymore, because no one uses it anymore...
)
If the transaction fees get high enough, then less people will create less transactions (because they don't want to pay the fees).
Which would essentially kill the idea bitcoin was once build on -- being your own bank is becoming pretty hard when you need to pay 15$ in fees for your 5$ coffee.
People will simply start using services like poloniex to do their transactions, which only charge 0.0001 to make a transaction. *Centralizes*
