I think the only common challenges that I see in bitcoin is high transaction fee and price stability of it. In my experience that is the only common challenges I faced is this two have mention above.
OK... I made a list of the common issues. Here it is:
1. Hacking of wallets
2. Lack of legal clarity
3. Tax complications
4. Volatility
5. Transaction fee uncertainity
I agree to you. That are some challenge that hard to address and need to avoid in bitcoin. But the question is how it will address and who is the responsible person will address the common challenges experienced in bitcoin.