There are thousands of coins going around at present time. It is very difficult to choose from them but in coincapmarket under 100 rank coin will always going to be best for investment. At present time gaming and nft tokens has good hype and their market is definitely will going to boom. For me definable project is very good to but at their all time low price. In big coin xlm and ada has the power to take your capital to many times so it your choice and research what do you want to buy.
Why you believe both coin have such that power, i recently know that XLM in progress of deploying its first DeFi called Yieldblox with their turrets mechanism, but when i try its beta, its kinda a slow and complicated if compared with another similar project. I believe its not from Yieldblox itself, the turrets itself probably need some enchanments in the future, until that thing happens, probably XLM wouldnt have such a big power to rise, moreover ADA, i never trust that project.