Its annoying not having fast travel to get back from early game mining trips but at the same time, I think fast travel is a goal worth working for. Ive been using a mod called Ender Book for my 1.7.10 teleporting needs. It does what you think, sets waypoints for the cost of ender pearls. A network of portals you actually have to build and walk through sounds more fun, less cheaty and best of all you dont lose them when you die. So maybe Portal gun does have its place after all, because I could disable all but one of the portal gun recipes so you can only have one portal for quick jumps back and forth and need more permanent solutions for everything else.