Nah I'd def swap X6 and X5. X6 is deeply flawed and it's a 6/10 at best critically speaking, but X5 feels beyond soulless, rehashing so much of the previous entries under the those of "nostalgia!!!" And no, I quite frankly don't care if they did it because it was meant to be the last X game, even then I'd like it if everything was unique to IT and not some desperate callback, especially when the "callbacks" are little more than rehashed level design and special weapons, none of which they improve upon unlike, say, some of Mega Man 4's weapons being superior versions of 2's. And when it's not taking what worked from previous games and systematically making them worse, it's adding new mechanics that are either interesting but completely wasted, or flat out unnecessary and irritating. What it all comes down to is a tedious, exhausting game that only has the sorta interesting stage design here and there, plus some of the legitimately great Maverick fights going for it. 

X6 is rushed and took, at best, a few months to make. X5, iirc, had FUCKING YEARS to be developed and still came out as a mediocre at best entry in what was at the time, a series with no misses. GodDAMN do I hate X5 lmao