Yeah if you're on the fence about removing one of those branches, don't do it. It's harder to put them back on than to take them off.
Thread grafts are definitely a lot easier than approach grafts. I've had some success with approach grafting roots but have never done branches.
With a thread graft, you simply drill a hole the same diameter of the material you are grafting. Drill exit side in. Then insert the thread through the hole until it is snug. It's nice to have a bud within a half inch or so from the graft site. This way you don't have a long internode before it branches again. Then you seal both sides with cut paste. Once the exit side starts growing strongly, you know it took.
For donor material on branches you can use a long whip branch and loop it back on itself into the thread. For grafting roots, you need seedlings.
Hope that helps.
Cory