Controller Replacement

Hello everyone,
I’ve been reading several post to help me chose my next ZWave controller but I am getting more and more confused when I read about zwavejs2mqtt and other stuff like that… I’m seeking a solution to upgrade my current VeraSecure master controller to another ZWave controller that is more powerful.
At present, my “master” manages five “slaves” controllers, each handling between 40-50 devices. Additionally, I’ve developed numerous program-logic snippets (some quite intricate) on my master controller. However, my VeraSecure master controller is struggling and has become sluggish, indicating that I may have reached its operational capacity.
I’m curious if HomeAssistant can function as a “master” and seamlessly recognize my five existing “slaves” along with most, if not all, of my current Z-Wave devices. Ideally, I’d like to avoid the tedious process of excluding and re-including each device individually.
Furthermore, I’m interested in understanding the hub’s programmability. Does it have a specific programming language, or is there another method for programming? Additionally, how flexible and powerful is the programming capability of this hub?
Thank you for your insights and assistance.
Claude