best would be converting to fiat, but if you assets are in altcoin exchange like binance, the transaction fee and the selling them for fiat pair exchange fee will apply. And same apply when you going back into it again. Converting to USDT with lower exchange fee maybe better and the ability to go back in again when opportunity presents without waiting for the transfer. Ultimately you have to consider your own opinion of the market going ahead, does it outweighs the short term fee and effort
Good luck =)