It looks like MSFS 2020 will have a number of missing or problematic things (helicopters, effects, etc.) at first release. It is a giant leap in terms of detailed scenery around the globe but, as with any new sim, there will be many things to be fixed/added later. I also don't expect it to offer those beautiful scenes in Alaska which lacks high quality aerial images and good OSM data.
For me, MSFS 2020 will be the "fun to fly around and sightsee' sim expecially outside the Orbx region areas including TrueEarth. TrueEarth US Washington, Oregon and Northern California are truly spectacular. It will be interesting to see how well MSFS 2020 runs on my 5 year old processor. (4790K) which is only a quad core.
inside the Orbx regional and TrueEarth areas, I will still be flyhing P3Dv5, most of the time, which has become super solid for me and much faster than P3Dv4. The only issue I have is those darn blue outlines on some of the trees without EA (enhanced atmospherics) turned on. That needs to be fixed. I don't use EA since it adds .5 or .6 to my available VRAM which has become a preciouse commodity. Also, I hate the pixel flashing issue, when clouds meet the terrain horizons in EA mode, even more than the blue outlined trees.
It is a great time to be a simmer with not one but three front line Sims to choose from: P3D, MSFS 2020 and X-Plane.
Rod