My biggest problems with Bitcoins is if fluctuation of the price comes.
and then sometimes my transaction is extremely delayed before my confirmation
comes in into my email

Right but at the same time we also have to understand that there are fellow bitcoiners who earn a lot of profit with just this. I love how the price fluctuates and gives us opportunity to earn with it.
Exactly someone takes price fluctuations as a threat and some view it as an opportunity to make quick profits, and people will really hate if price remains stable for a long time.
Yes the price fluctuations and curiosity of guessing it brings entertainment to bitcoins and separate it from others.
I think I view it as a opportunity, but for me in bitcoins there is just one problem, sometimes confirmation time, that's it.
The fluctuations is the very lifeblood of earning for us traders so of course, we don't hate it. Rather, we absolutely love it.
I would have to agree with the confirmation time as the biggest problem with bitcoin because it has become slower and slower. At times, it takes my transaction to be confirmed at 4 hours which is obviously bad for business because we want instant transactions.