Thing is? Warlock Punch is not only something that fits with his moves, it fits his battle style way better than a slowly created projectile ever could. Those just leave him super open, and doesn't actually fit his playstyle(which is a brutal but slow beatdown, something he's more than open to doing within the games, quite constantly). Ganon/dorf is a character who can and will body you hard. And Smash actually exemplifies him a lot better than was expected. He does not do "fast projectiles". Even the Blazing Bats is intentionally slow. That's honestly the point behind them. Ganon/dorf is a larger character, and there's barely any fast projectiles(which don't make to put on a heavyweight either. If it's going to be a projectile that can do more than damage, as in pushing people around, it's always a bit slower to balance it correctly. Ridley's only projectile has little force behind it. Same with Bowser and Charizard's, who are all power-based characters. The stronger the projectile is, naturally the slower it is to make it useful).
Volcano Kick on the other hand is nothing like any of his moves or animations, and basically needs to go. Dark Dive is his only special right now that has no reference and is actually pretty bad. Warlock Punch, unsurprisingly, is also referenced in Hyrule Warriors and has become a minor signature move for him as well(same with the Reverse version). They're just a core part of him nowadays.
He also doesn't do projectiles that much anymore, more focusing on brutality at times. He's a physical character quite often, and his moveset is extremely fitting to his current style of characterization. It's just two moves do not work at all. Removing one of his most fitting moves also does not improve him(as noted above, the only kind of projectile that works is a slowly created one, as it's the types he actually consistently has used at any point. Mainly because he borrowed from Aganahim. Incidentally his moves have become his own(and often generally physical) that doesn't copy from others. Smash coincidentally has used and help influence his abilities slowly. Instead of copying an old character, he's now a physical powerhouse in canon, which is also when Brawl was able to use his new animations and concepts already inspired by Smash. It shaped who he is, giving him a real identity.
It would be nice to have a clearly better magical ability, but it's very difficult to pull off with a slower-paced character, without making them significantly worse. He's already using lots of magic in his physical attacks. The best is able to not remove better moves like Warlock Punch and makes it an optional move, like an extra move he can do. Much like a few others have secondary moves, holding down the A button to create his Energy Ball, and then throw it. It's also designed better in that it's very difficult to reflect(outside of normal reflective moves), but more or less can follow the canon well with a "only a Smash attack can deflect it", with a spinning version or moveable to reflect it(and only in the sense of something like Spinning Kong, not just the Screw Attack), making it actually interesting and making unique matchups. Meaning not a lot can actually reflect it outright either.
Otherwise, he needs an actual Reflector. His Forward Air is the best and most obvious example of it, since it's basically a Volleyball Strike~