You are correct. The fees have risen and people often send btc with the default fee set in bitcoin core,even if the slider is set all the way to fastest its still not enough of a fee. You need to set a custom fee otherwise will be hours upon hours to confirm
I used the deposit using BTC function of the ethereum wallet.
It gave me a deposit address and told me that it will be converted into Ether and sent to my Ethereum wallet address.
I'm still awaiting its arrival after 24+ hours
Did you check the BTC deposit adress you were given via BTC-blockexplorer if your payment from multibit wallet went trough?
Bitcoin has a lot of unconfirmed transactions these days, so small amounts can take some time to reach its destination.
djoser.