It's what you can get with other trading platforms that are worth the money. For example, I use WEX Home - WEX (tradewex.com) They offer features such as a COB (complex order book) viewer. I can see and interact with spread orders that are resting in the various COB's and the spreads are sorted by value. I can automatically hedge any option trade I make against stock. I can trade solely based on volatility. I can trade different products against each other automatically, such as stock vs stock or options in different stocks. I can easily have multiple option and spread screens up. I can direct orders to any exchange. And many other features. If there is any problem, they will answer the phone on the second ring. Point is paying for a platform can give you many more opportunities than some free ones.
They have multiple lists you can use as your watchlist. I review and pick the ones I like the stockchart, usually stocks trending up or down strongly. I use Finviz.com too to compile other lists. Not going to trade each and every stock in the list but, narrow it down further, based on my criteria. You can trade the same ticker symbols in your watchlist.
For the last 15+ yrs ... I only day trade a handful of stocks ... usually staying with 1 stock for several months or a couple of years. Those being INTC, MU, ROKU, FB, AMD and NVDA. - Peace out