Security ?  I think all good exchange do also come with good security but its not enough because no matter how good the security they have , there is also a chance that a hacker can bypass it and steal all the funds that the exchange have  .  and when it comes to fees , i dont think that there will be exchange that will have no fees because they will loose since we all know that everything in crypto needs a fee to be able to process a transaction  . the fee wont go to the owner of the exchange but it will go the miner  .