I'll make up a patch for you on the URL target. It will probably include the delete link stuff, but that is pretty easy to strip out. About the delete link, I can seen the concern. I go through a lot of bookmarks, so I like the convience.
While we're on the topic of links, I think it would also be nice/neat to implement some of the functionality from bookmark4u into mojoPortal, most notable the ability to group links into categories, and then display in some sort of treeview. Maybe create something like a TreeViewLinks module?