It's probably better to just move the titles you don't want to see into a folder on the last page.
Theoretically, someone could probably create an app that issues the needed MCP commands to delete the wanted titles, but this will likely come with a bunch of unintended side-effects. For example, deleting Mii Maker will likely prevent you from being able to create/modify user accounts (which launch Mii Maker to allow you to select/edit Miis), deleting Wii U Chat may not work at all (what would happen when you get a call?) and deleting System Settings/Parental Controls is just asking for trouble. You could make a case for deleting the Play Log and Health and Safety titles, but again, I wouldn't recommend anyone try this without a NAND backup and a means of restoring such a backup.
On top of this, deleting the titles might not even hide the icons from the menu (its possible that the system title icons are hard-coded). Nobody has ever tried deleting these titles (at least to the best of my knowledge) and so there's a lot of unknown information on this topic.
