I use to trade in short term. I choose a coin which have regular predictable waves (+-20-30%) and set buy and sell orders on the bottom and top of these waves. And it most cases it works for me. I also tried the strategy that you described but it's applicable only for a long term trading.
I do the same. For me, I join ICOs get their tokens and then use it as capital to buy low priced coins that I could dispose for a little but okay-ish profit. I have set my eyes before on the big players like Bitcoin and Eth; however, I don't have that much capital, and since low cost altcoins could be easily bought and have more chances of at least increasing value from half to double of what I bought them for, then I began to think that it would be more effective to trade them than trying on those higher valued ones. At least with the low tier altcoins, I could buy more and I could dispose easily not worrying about major market trends and movements.