The
Mini2 won't fly in winds much over 10mph, but the
P4 will fly OK in 20mph winds, in case that's important to your area. The
Mini2 will have a greater radio range and flight time, and it's very easy to backpack while hiking or biking, not to mention super easy to take on a plane for vacation. It's not a bad upgrade, and if you use it mostly for travel and recreational use, the
Mini2 is a good drone for that. It's VERY quiet, that's what I like about it. I can sneak up on animals much closer than any other DJI drone.
IMO the
P4 was DJI's most anemic drone they ever released for range. It was the stock GL300C controller that caused it. The previous P3P would go twice as far. You can fix the range issues with the
P4 by using an Inspire GL658A controller, that's what I did back then. The replacement
P4P was a big improvement to the
P4 for range.
I happen to have a left over GL658A if anyone is interested.