There are some factors that need to Notice before Investment on any Altcoins.
Market cap of that Coin
24h volume of that coin.
Maximum supply of coin
Blockchain Technology that Coin is using.
Globalization
Community behind that Altcoin
Whitepaper
Liquidity
If I missed anything then include this in this Topic
You write that very correctly.But sometimes these are not enough. You should always follow Altcoin news. Every step in coin develop very important.