For me to find a decent altcoin, it must have several important requirements,
is that the altcoin project is active in social media because social media is a fairly effective communication,
a road map that is already running well, a strong and experienced team, and a few more conditions.
and of course, all must be done with analysis first
I think the most important point you made is that an altcoin is worth investing if it has "a strong and experienced team". If a team is capable to achieve goals and has a strong community supporting them, then the project is already 50 percent successful. Also, there should be very good project backings. For example Injective protocol is backed by Binance, this gives investors some level of hope. Whitepaper and Roadmap nowadays can be well written / designed but yet the project is scam, hence even though I check through to know project aim and milestones to be achieved, it's not really what makes me invest in a project.