My question is, what is your accepted gain/loss % before selling the coin? If you get 5% should you sell it or just wait for it to continue growing?
You should know one thing that nothing will grow continuously up. So you should set a limit for booking profit and losses. It is not a bull market so if your reach more than 10% profit then try to book some profit and invest in other coins or keep cash to invest back when prices come down.
I would probably hold to some altcoins for the long term when I have more cash to play with.
Not altcoin but try to hold some BTC for a long term because it is a better coin compared to altcoins for a long term. But if you more fund then choose few other coins along with bitcoin to hold for long term.