Keychron would be my choice because they have open source QMK/ZMK firmware, a decent web-based configuration tool (Keychron Launcher) that is built around an open protocol (VIA) with their own open extensions. The build quality is good and they are customizable (hot swappable switches, standard layout so keycaps are available). They have a bunch of models so you can find some cheaper options and some more expensive premium options. I am quite fond of the Q series which have a solid aluminum body but these are the expensive ones, the K series tend to still be great keyboards but with a more affordable plastic or plastic/aluminum hybrid design.

As the OpenRGB creator, if you care about RGB, especially if you want to sync with other devices, stay away from the no-name boards with closed source firmware. Might have good build quality, but their firmware situation is awful and you likely won’t be able to control it from anything other than the official app, RGB sync is out the door on many of them as they don’t have an RGB streaming mode.