It's not enough having an investment plan, knowing the right choice to make for every investment defines the investor better. Take for example jumping on every new coin we find on reputable exchange might not be enough guarantee that coin will do well in the future.
Some coin might have good Supply but low liquidity, some might have high market capitalisation but very poor volatility. Although it's hard to predict the accuracy of a coin performance in the near future this why it is always advised to stick to the known which is BTC.
Another option is to spread ones portfolio amongst different coins but ensuring the have a greater percentage in projects with a visible future. It is better to win small and lose less than lose more and win less
this is the reason why you actually only have to invest in bitcoin, even though the majority of altcoins are still cheap, altcoins are centralized assets, while bitcoin is a decentralized asset, wise people will definitely only choose bitcoin as their investment, besides that the liquidity and price volatility will be very high affect the profits from the investment made. The very important thing that always saves investors from losses is that wise investors will not easily suffer from FOMO and FUD, they have good fundamental analysis and Bitcoin is usually the choice of smart investors, not altcoin.