If you really want it, it is not too much trouble. I hear there's not much to it at all. I know someone that got a vasectomy for the same reason. He and his wife have 3 kids and get pregnant very easily. He got this done because if they decided they wanted another one later, it was much easier than reversing anything she would have to have done. I have 5 and may even have 1 more!!!
If you both want another child then any task will seem small. Reverse the vasectomy if you want another baby. Children are worth everything! but seriously consider what you have posted. You both my like the idea of another baby, but having the child is a different matter all together as you very well know.