As a lens to get going the Z24-120 f4 makes sense, reach for longer distance wildlife being the only week asset. The performance of the lens in all other areas is well noted.
I have the F mount version and find the bokeh the be pretty good for f4 and in low light works pretty well. Faster lenses do give "better" low light performance technically in the cases where you can open them up. The tricky part is getting the focal plane flat enough to open a fast lens the whole way up. I find in "general" shooting (hoping to read your desires correctly) I have found its much less of a "requirement/need" in my experience.
For a lens you will want to keep I think it is a great choice that will see a lot of use, the Z24-120 f4 makes good sense. I find it to be a great landscape lens as well as flowers (close stuff). I think it will serve you very well, its popularity (actual street value) would also allow you to trade it if you hate it.
Hope this helps