@ReinierB You have an almost complete set of all excellent optics. I also think adding a curio makes much more sense than adding a Habicht.
I am also a person who loves high powers. I always feel like something is missing when use NL 8x42, and of course it is the magnification. However, with the Curio it is not the case. Surprisingly with Curio I don’t get that feeling of missing magnification. I think it is basically because of the less FOV of it, that causes the object we are looking to fill a higher percentage of FOV. And of course the extra stability of 7 power. Moreover, I believe Curio is extra sharp and contrasty compared to the NL 8x42. However, I didn’t compare it with any other high-end pocket binoculars but I am perfectly satisfied with Curios.
On the other hand I had a different experience with Habicht 10x40. I bought them to use in low light conditions where UV 10x32 is too dim to use. And I had some hope to get the advantage of 3D effects that is inherited with porro design. However, I didn’t not see it at all, maybe due to my less trained eyes. Indeed they are bright -I felt it has a similar amount of bitterness compared to NL 8x42- but I failed to harness the advantage of using them as a low light pair of binoculars due to the reflections occurred in using under above mentioned conditions. Again, you might have the same problem or not and that will define by your face shape. As the final word of all, the best thing is try them with yourself. Binoculars disliked by on could be the perfect pair for another person or vice versa.