I aim for 75-100% broad market index funds (VTI/VXUS), and a maximum of 25% individual stock picks, with no more than 5 individual stocks at any point in time.
Individual stocks generally going inside Roth, to capture maximum upside with zero taxes, but I also prefer to keep at least 50% of my Roth in index funds in case the stock picks don't work out. Any overflow of individual stocks goes to Trad IRA or taxable brokerage.
I think going fully VTI/VXUS likely is the best strategy for the vast majority of retail investors, but a small concentrated and strategic allocation of individual stocks can scratch the itch and allow you to outperform (or underperform) the market.
Lastly even with stock picks I don't day trade. I generally aim to hold my stocks for at least a few years before trimming or cutting. Day trading is mostly noise and requires extremely high luck, on top of being lucky with your stock picks.
Oh yeah and stay away from Penny stocks.