Godot is probably the most similar to Unity. Unreal Engine could be an alternative if you're looking to also upgrade graphics and don't mind more difference from Unity. Finally Bevy Engine if you're looking for something completely fresh (ECS + Rust) although still early in development so not as batteries-included as Unreal, Unity and Godot.
Godot is amazing for 2d. There's basically zero reason to use Unity anymore. For 3d it's still a bit rough around the edges, but gaining traction fast. If you want high tier 3d you're probably better off with Unreal, but IMHO it has a significantly worse DX and it will only start to shine when you work in a big studio.
Honestly still a question worth investigating. I also dropped Unity for my latest project, spent a year with Godot and then realized.. it's just not quite there. So I had to go back and rework things. One thing you realize quick is that the talent pool for Godot is unfortunately very shallow.
Post publish, I will probably try Unreal and see where it takes me. I think Tim Sweeney has brought some good ideas to the space, so I am more willing to hop on his bandwagon.
Yeah, I'm definitely going for Unity since I'm exploring XR. But at the same time I'll also look into Unreal which will take longer anyway. (The features seem to be quite amazing, also integration with 3D animation software)