im prefer to buy more on etherium, if you really want invest, hold your eth and btc until 2021, you will get big profit like 2017 did.
In comparison with ETH, Monero has not so bright potential, but it is the altcoin which will be always in demand. If you want to earn a lot, it is better to pay attention to other cryptos like Eidoo and BNB - they like to wave greatly.