The question says it all...what coin has the brightest future and is worth HODLing ?
Right now ETH seems to be very low and undervalued but I would also go for Monero. Go 50 / 50 is always a good decision to avoid risk. I don't expect Monero or ETH are going to fail, but if one goes to moon and other not or only a little you'll make a good profit by averaging price increase. 