Recently, I would choose Cardano ADA. And I really think in the long term, Cardano will be a top coin more than LTC (which is just like a prototype of BTC). Cardano has its blockchain with pos consensus, arguably better than ETH.
Personally, if I had to invest in any of the two, I would choose Cardano; put it for staking on exodus wallet and let it grow while Cardano go bullish.