Well bitcoin is still the best option here when it comes to long-term trading.
I don't know altcoins that stay longer and perhaps ethereum will be the next to bitcoin but since it is a centralized one there is no assurance to stay longer than the decentralized coin like bitcoin. However, the highest leverage is those altcoins that have potential but if it is higher leverage which means also a high risk which most traders are afraid of. Bitcoin is the best option and I highly recommend it to anyone.