>>720165020 (OP)
I also find myself replaying 2 much more than the others. I can't explain why but it's a definite favorite of mine.
>>720174106
skytown felt really samey to me everywhere except the shoehorned metroid laboratory section. I had to constantly check my map lest I find out that i've been going in the opposite direction to where I wanted to
Prime 3's upgrades were also kind of lame. Sure, P2 had the lousy seeker missiles, but P3 has the grapple lasso (no you can't use it to cross pits, we just need an excuse for you to shake the nunchuck) and the hazard shields.
Hypermode is also broken and kills everything easily for [mostly] no cost. Despite this however, I remember the phazon shots feeling really weak everytime I used them. Just the standard beam makes the satisfying *pew pew pew* noise and you can see it scorch the ground when it misses, but hypermode looks like you are spewing a bunch of blue party streamers that somehow kills everything it touches.
Pirate homeworld was really good though, and the final dark samus theme is great.
https://www.youtube.com/watch?v=QFOqGV-6bck&pp=ygUebWV0cm9pZCBwcmltZSAzIG9zdCBkYXJrIHNhbXVz0gcJCbIJAYcqIYzv
Other hunter fights were good too.