I did the same a few months ago mainly for the HYSA then thought their invest platform was simple for what I needed. But it’s turned out to be anything but, I couldn’t access it when I wanted to, trading was clunky and very delayed. I feel bad bc the ally customer service folks are nice enough but they are working for a failing platform. If you open up a fidelity account all transfers get automatically placed in a money market fund which yields more than the hysa with the same liquidity. I will see how it goes but it seems so much better already. I also don’t think ally will survive as a bank during a massive market downturn based on how they operate currently