Suggestion for a new setup, coming from a GoPro and wet lens

Hello, like in the title, I think I am ready to start considering an upgrade on my equipment.

I am currently using a GoPro 12 with 3 inon wet lens, with tray, floater, and a tripod for shooting macro and video with fixed camera

I am now evaluating what will be my next system, since with the new mission 1 realese with new form factor, and new high price, I am oriented to go on the next level, but I feel overwhelmed a bit by the choice.

I don't have an exact budget yet, but since it's an upgrade on the current one, I start evaluating system from 2500€ and up.

I'd like a suggestion on the camera body, lens option, tray and lights, but mainly I have to decide the camera.

I'd like to keep the GoPro flexibility under water, where I can swap the wet lenses from wide, to macro, to super macro, ( by this I mean I'd like to have a system that allow me to be able to shoot almost everything without the need for example of a lens change inside the housing), to have a good balance between performance and size, without being too heavy to travel.

Also, the size of the setup underwater would ideally be not much bigger than the current one, to allow me to film in small spots.

Here is a picture for reference of the current setup

Edited 1 hour ago1 hr by Elvandar