I think the biggest disadvantages would be the high fees es you have to pay to sell your bitcoins because i just started and when i did my first selling of bitcoin i payed a lot of fees so i was not very happy with that.
If you are not happy with that then do not stick with bitcoin. The fees in transactions are high because the miners are not working hard for a small reward and because the amount of the bitcoin user is going up, they need more reward so they can attract more people to mine bitcoin and continue supporting the blockchain. So it is very clear that it is for the bitcoin and not by just for the miners.