Whenever you mention Altcoin, my mind first goes to Ethereum, if the Crypto boom started right now, I would be among the first people who would buy Ethereum, atleast add to the ones I already have, I love Ethereum because it's one of the easiest blockchains to use and I am conscious of the contributions that Ethereum has done to the development of blockchain technology, another coin I would consider purchasing is  XLM just out of pure sentiments because the XLM airdrop was one of the best Airdrops I ever participated in.