Uncoupling the "add new" options in the timeline module and the add new submenu

As you can see on this screenshot, I have a big list of items next to "Add new" on the timeline block, and I'd like to keep just 2-3 items there.
I'd like to keep the rest available in the submenu, which drops down when I press + (Add new).

How can I individually manage these two "navigations"?