I really love the first point which states "investing in several top altcoin (spread your investment)," emphasis on the top and established altcoins. I believe that by doing this one can minimise the risk level of losing all in altcoin investment. Patience is the key as well.
Top coins are safer ones for investing. The ones that best known by the majority. After the fall, most of the projects turned into shit and scared most of us, and in this case, the better place is safe place.