Changing platforms, best for APIs and Margin?

I've been on eTrade for a long time, and it's done well by me, but doesn't seem to be competitive at all when it comes to margin interest. That didn't matter in the past but now I'm routinely using it and the interest is adding up. I don't think a small fry retail investor like me can get them to give me much of a break on that, especially compared to the 5% range rates I think I'm seeing offered by other brokerages. Etrade is in the 11% to 12% range.

I am also using eTrade's APIs for a custom app I use to trade covered calls. Their APIs are adequate and have been reliable although I wish they were a tiny bit more reliable (e.g., they usually don't return back next earnings date for a ticker).

I've done some research and public.com and interactive brokers both seem API friendly with good margin offerings.

Does anyone have any suggestions for me to further my research?

TIA.