Your argument basically revolves around explaining every little thing in the movie. Jesus maybe Finn previously drove speeders at some point for the first order and not TIE fighters that’s such a retarded argument. It was irrelevant to the plot of the movie. Plot holes in older Star Wars movies get to be explained away by authors of the EU 20 years later and no one bats an eye but apparently TLJ killed someone’s kid or something so it needs to be scrutinised down to the atomic level a month after it comes out.

Yes, I’ll agree the Finn rose ‘thing’ whatever there relationship was was poorly done, the whole side plot to the rich people planet was ehhh and Snokes lack of back story and character was also pretty poor but I can see why they cut him as he’s basically a caricature deformed evil bad guy and having Kylo at the helm makes a lot more sense. Definitely missed opportunities BUT

Luke and Holdo were actually going to be achieving things when they sacrificed themselves. Watch the freaking movie and you’ll see Finn is just gonna get vaporised before he even crashes into it. Rose should’ve probably said something along those lines since clearly people need things spelled out for them.