I disagree with DB6, I think it is still a useful and dare I say it an enjoyable tool to use. Yes you will probably end up navigating mostly by GPS/VOR but it is still useful to draw lines on a chart and calculate and fill in a plog as well, for the much greater situational awareness compared with just using goto on the GPS.
I may be perverse, but I also get a measure of enjoyment from planning my flights in advance and a great sense of satisfaction when all the headings and timings that I have calculated work out (maybe I should get out more). Lastly when the electrics all go out (it has happened to me) my plog, stopwatch and chart will still allow me to navigate home!
So I say stick with it and keep practising eventually it will all make sense and it them becomes quick and easy to do the planning.
Nigel