36: Tekken 6, maybe?

42) I've heard most about Warlords Battlecry, but the hint makes it sound like it's not an RTS one, so... Warlords II?

38) Sonic Adventure 2?

You're in the correct genre.

Correct on #42 (it's the vastly expanded Warlords II Deluxe version), wrong on #38

Two new ones, and new hints for the earlier two.

40 - In a live-action cutscene, your instructor in one level, as you fly one of the enemy's craft, casually refers to your enemies as "Bucketheads".
Hint 2: You'll also have to "follow his lead and do what [he] say".
Hint 3: It is strange though, training rookie pilots by letting them fly enemy fighters at high speeds through extremely narrow chasms. Doesn't seem safe. But this is important, because (in the story anyway), you'll need the knowledge for the capture of the enemy's experimental cloaked fighters that have been wreaking havoc. Guessed by Bofferbrauer2 - Star Wars Rebel Assault II: The Hidden Empire

38 - The single-player mode of this game, the base game anyway, features campaigns for five of the six civilisations, though a mini-level of the sixth can be played as an easter-egg in one of the levels of one of the other campaigns after you find it by revealing the map through a cheat-code.
Hint 2: There are still six campaigns anyway, but the first, which is a tutorial, and the last campaign both feature the same hairy civilisation.

37 - Green, Red, Yellow, Blue and Orange, are the colours to focus on, from left to right. At least it didn't yet have the purple bar as well. Guessed by Veknoid_Outcast - Guitar Hero III: Legends of Rock

36 - While still great, the expansion for this game tainted the balance somewhat, because the new civilisation could use certain powers multiple times while the original three can only use every power once.

I feel like #37 is a Guitar Hero game…maybe Guitar Hero III?

You are correct of course. Seven correct ones for you.

The colours alone hint at the fret buttons of Guitar Hero (though I guess it could've also been Rock Band). The second part hints at it indeed being 3, because that one didn't have the purple bar (representing an open sting on bass or foot pedal on drums) yet, it being introduced in 4.

Nice! I still have my two Les Paul wireless Wii controllers for that game. Lots of good times :)

Street Fighter IV. I found it weird that Rufus and Bob got added to their respective series at the same time.

I played Supaplex a lot back in the day. Solving one more level or retry after failing was a very addictive loop. This game in it's core is a Boulderdash-clone, but added some things and had such neat artstyle and sound-design.

As in Boulderdash you go through the level, collecting (in this case) Infotrons and avoid being hit by a stones. The game includes exploding floppy disks, enemies (the scissors you see above), gravity for some levels and some other stuff to keep it fresh. If you collected the set number of infotrons for the level, you can go to the exit (if you didn't block it with your earlier actions). Overall it contains 111 levels, but if one level is too difficult, you can skip it, but the number of skips is limited. As usual with puzzlers, the solution often needs some good thinking.

One thing that I liked about the game, that sound-design and the background melody are seriously addicting. The graphical design with the computer hardware theme (sorta) is also quite cool.

The game released originally for Amiga and DOS. But it got many clones and rereleases like Megaplex for Windows (with level editor), Infotron for MacOS, Igor The Time Machine (an extended game from the same devs), WinPlex, New Supaplex, Supaplex 3000 and an adapation for the Apple Appstore. If you want to play it, you have certainly a lot of options. For the original feeling, download it from the developers and play it in DosBox. Also an open source reimplementation exists, to bring the game to modern platforms.

https://www.youtube.com/watch?v=wYzIGnw3KHw&ab_channel=RXQ79