Personally, I will stay away from Robinhood. Gamification of investing scares the cr*p out of me. You WANT investing to be boring - not confetti-and-sounds exciting stuff.
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There are many other established players, including Vanguard, that are perfectly great at being a boring brokerage.
Vanguard:
Pros - more trusted, with a long history of prioritizing and looking after customer interest (e.g. no bull** low cost index funds). Pioneer of the indexing trend.
Cons - clunky user interface. Think of them as old style paper and mail brokerage that have slapped on a website as an afterthought.
Fidelity/Schwab:
Have a history of trying to pull a fast one on the customer in distant past (in terms of fees etc.). Recently, however, they have started catering to the indexing investors by offering appropriate index funds and not trying to pull too many fast ones.
I personally use Fidelity, and DW's 401k is in Schwab. Just make sure you don't sign up for the "managed" funds that they will advertise from time to time.
Much better UI than Vanguard.
There are a bunch of other brokers - Merrill/TD/JPMC youinvest. All of them have low cost options that are perfectly acceptable.
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I will repeat - if you are feeling an adrenaline rush while placing an order, or after placing it - please STOP immediately and make sure you fix that (change strategy, change brokers, adopt index investing, read JLCollins linked above - something, anything, to make investing boring again).
You WANT investing to be boring, not exciting!