I've loved this mod ever since its very first version in 2.1. It's genuinely a shining beacon of how much one can love a series. All the details, all the references, how you've managed to implement tricks from Super Metroid into a 3D space and make it work in a Sonic game! I've never played a Metroid Prime game, but I have played Metroid, MII:RoS, and beaten SM. This actually encouraged me to play the latter of the three.
Even after making what felt like a perfect mod, you've managed to make it even better! The new maps are a very welcome addition, and the new bosses are exactly what Samus needed to feel like there was a challenge before the endgame and outside of Hyper and Fusion mode.
If I had to give any criticism, it's that a lot of the enemies in Hyper(+) are extremely touchy and sometimes downright obnoxious in the case of Pyre Flies, Egg Guards (I played an outdated version so ignore this one if it doesn't apply anymore), and Gold Buzz's.
-Pyre Flies take up a huge amount of space, sometimes forcing you to fire at them long before trying to platform, and slowing the pace in what is otherwise a fast-paced endgame.
- Egg Guards on the bridge, and pretty much anywhere else, are just... actual pain, and cause the same problem as Pyre Flies, slowing the pace down to a crawl until you demolish each last one of them at points where you just want to speed and not get sniped by a Robo Hood.
- Gold Buzz's are... well, obvious. They'd be fine if there weren't so many of them in THZ1, and if the Emeralds didn't require no-damage runs. Thanks to the combination of circumstances, it makes Gold Buzz's excruciatingly painful unless you have Wave Beam or are really good with your shots.
Even those enemies aren't enough for me to falter on giving this 5 Stars. This is just *the* best character mod SRB2 has ever seen. Worth every minute of wait.
1: Try give Fusion Mode a shot, you probably won't find it so easy! (don't do it on "new game plus" that time. :P) If even that's easy, try a low% Fusion run. If you find THAT easy, try entering eSports.
2: Turning special stages back on IS an option in the ship, actually! I just personally think they're repetitive for anybody who's collected the emeralds before. NiGHTS special stages use the same gameplay for all characters and break the Metroid spirit.
3: I got really burned out after the ACZ4 and DSZ4 bosses and stage and would've had to delay Metroid Vanguard and give up on SA-Sonic if I continued. Glad you're up for more content, though!
4: It being Fang is moreso an easter egg than anything meaningful. The Sonic cast isn't really related to the mission or ever brought up. Samus just got fed up with Eggman's intervening and extended the mission to take him down. (Really, just an excuse to keep playing through SRB2's campaign. The story was written around SRB2's campaign rather than vice versa.)
The "Blue" Fang wrote on the wall is a warning not to approach the nearby Phazon. (Which is blue.)
5: Was meant as final stretch base-storming hype music. The game's a cakewalk after ACZ4 until Brak catches Samus off-guard.
That's my thoughts! Much as I love Metroid Vanguard, I might not approach it again in the future. But then I did say that before and the 2.2 update ended up alot more ambitious than intended, so who knows!