Space Gun is the easy bake aim weapon besides. Its main advantage over Flintlock Pistol is that it has about 1.5x the velocity and 2 extra pierce, the latter of which doesn't really matter for Skeletron. This does legitimately give it a niche for Queen Bee in some cases due to how fast she flies around, but its awful damage combined with Queen Bee's scaling defense really hurts it in this niche.
Also, Space Gun isn't slower than Flintlock Pistol, due to niche but ubiquitous use time mechanics. A weapon that has autoswing will attack for the duration of its use time, and if the attack button is held on the final tick of animation, the animation immediately starts again on the next tick. So Space Gun fires a projectile once per 17 ticks with no modifier, 15 with mythical. A weapon that does not have autoswing will attack for the duration of its use time, then stop with no check for autouse. This forces 1 tick where the player is doing nothing, and this tick reads the next attack input to start using the weapon again. This applies even with autouse turned on, so Flintlock Pistol fires a projectile once per 17 ticks with no modifier, 15 with unreal. If you were to have a weapon like Clockwork Assault Rifle or Golden Shower but remove their autoswing, I'm not really sure how this would work, but I'd imagine it would be analogous to Starfury where the projectile comes out whenever the item animation is active and the cooldown is at 0.
Speaking of Starfury, I mentioned the melee speed tick and no one asked about what I meant. I'm sad. Y'all learning what the melee speed tick is now. So when a weapon's use time is affected by melee speed (i.e. spears, swords, shortswords, but not boomerangs or guns), its attack cycle is actually 1 tick faster than what the melee speed calculation would suggest. Break out OBS and check it yourself, base copper shortsword with no bonuses extends the sword for 12 ticks before it gets put away for a tick then reused due to no autoswing, legendary fetid baghnakhs with 1~66% melee speed have a 5 tick swing animation despite the calculated 6. This is something the devs have been aware of for a while and something you saw highlighted in old Baghnakhs builds reaching 1 swing time with 134% melee speed, but no one really talks about it. Because this tick is lost after melee speed calculations, it gives a bigger and bigger bonus the faster the weapon is and the more melee speed you have. This is why 134% Fetid Baghnakhs used to throw out 4x as many swings as 41% Fetid Baghnakhs, instead of the 2.5x you would expect from the math. And, why Fetid Baghnakhs and other extremely fast weapons were nerfed to only receive a fraction of their normal melee speed benefits. If not for the melee speed tick, this never would have happened - there's no other reason why attacking 1.5x faster would benefit the fast weapon more than the slow weapon, it's still the same damage increase. Baghnakhs now has melee speed thresholds of 1% for the first tick, 67% for the second tick, and the basically impossible 160% for the third tick drop, so generally I'd recommend treating it like Daybreak and just not bothering with melee speed, unless you're naturally near 67% somehow.
This means spears, which benefit from melee speed but don't have autoswing, have an effective use time that actually matches their listed use time, much like every non-melee weapon with autoswing does.
One final thing with autoswing vs no autoswing is that buffered hotbar switches only go through when no item animation is playing, which makes them clunky to use with autoswing weapons. Whips' lack of autoswing is what turns whipstacking from a niche, annoying gimmick that would sometimes lose DPS from human lag to a fairly widely useful but somewhat difficult skill.
