The way I see it, is that you need to invest in altcoins who actually innovates either by making crypto easier to transact with (platform coins like: ARK, NEO, Ethereum, etc.) Or projects which builds on privacy, (XMR, DASH, Zcash)
The days are over for literal SHITCOINS with no purpose. You need to bring something to the table, like any real company (Just like the stock market basically).
The market needs to mature, and it's a long long process.
Personally I'm betting my money on
Lightning Development for a couple of reasons:
Speed of transactions
Lower fees
A true gem, I've been eyeing is Stakenet (XSN) who's leading the development of Lightning with their upcoming Lightning DEX, and Lightning Multi Currency Wallet (With TOR integration for privacy).
I can see this project becoming really useful for transacting peer to peer, without the risk of getting your funds stolen in exchange hacks etc.
Also, no need for KYC, Registrations, or syncing up with their DEX.
Whatever you do, don't invest in projects with 0 to no development, and you should do fine once the market turns around

Now, which altcoin has a real purpose in our lives? A few that seems beneficial to people like Musicoin have very little support. Paying the artiste directly everytime listeners listen their music.
Until these projects shows tangible purpose, I believe many potential new joiners tend to refrain from diving in.
The rest of us are hodlers as there's little movement in the altcoin market. We need that spark, even how artificial it is, to get prices up and ourselves out.
That's the sentiment of many holders today I guess. Forget the whatever white paper projects.
Small time miners are affected too esp those mining eth with increase difficulty and reduced rewards.