Speaking of the last two points, realize that crypto tends to be pattern based and tends to go in cycles. See “the cryptocurrency rotation” and “market cycles” for an in-depth look at what this means. You want to be in a coin before it starts its rotation, and then laddering out as its rotation ends. Likewise, in a perfect world you want to be in for the bull part of a market cycle, and out for the bear part. Near impossible to spot these trends in advance, but with experience you should be able to spot them as they occur and manage your positions accordingly.
Always pay attention to Bitcoin. Most altcoins (every cryptocurrency except Bitcoin) are pegged more closely to Bitcoin than Asian currencies were to the USD during the Asian Financial Crisis. If Bitcoin price pump drastically, altcoins price can go down as people try to exit altcoins to ride the BTC profits; inversely, if Bitcoin prices dump drastically, altcoin prices can go down, too, as people exit altcoins to exchange back into fiat. The best times for altcoin growth appear when Bitcoin shows organic growth or decline, or remains stagnant in price.