Check out mod called "precision node". I always hated pulling the maneuver nodes around. Default node UI is BAD. This mod will give you additional node interface, you can easily move between nodes and it will also calculate and sum up delta-v of multiple maneuver nodes. There is node memory in case that you want to delete node and try different one and then restore previous one. As an extra, there are different projected orbit views.
Im also using mod called "Trajectories". This mod will project real planet descent trajectory with speed and atmosphere drag calculated. It is pretty accurate and helpful.
lamzor's comments