Captain Kaboom

I tried but it seems to be glitchy with me.

I'm really not a fan of how the Falx looks in-game, the thick, jagged blade looks kinda ugly IMO and the wooden spine coming from the grip that fastens to the blade is unrealistic, real swords used a tang, a blunt extension of the blade that the handle material is wrapped around. If anyone is willing and able to make a mod that changes the Falx models to a smoother, sleeker blade that doesn't have the wooden spine please hit me up.

The Halberd is a weapon that originated in medieval Europe and is like a cross between a battle axe and a spear, it found widespread usage in the late medieval era and effectively replaced Swords in many cases as the Halberd is much better at defeating heavy plate armour than any Sword. The Halberd would thematically fit very well into the game as Vintage Story seems to have a late medieval setting and the unnatural monsters are too tough to defeat with a traditional Sword according to the Falx's in-game description, so the Halberd would feel like a natural pick for the Seraph as they'd be familiar with it and it's superiority over swords at defeating tougher enemies. The Halberd in-game could act as a longer range and higher damage alternative to the Falx at the cost of it being more expensive to make (requiring a a spear & axe head, equivalent to 2 ingots) and wielding the Halberd disables the offhand slot as it's a two-handed polearm.

To add to this discussion there could also be anachronistic elements of firearms tech added and mixed together, like rifled barrels and minie bullets, though I think breach-loading would be a step too far.

Totally agree, bows absolutely should have a much faster reload than any muzzle-loading musket, just like IRL. But the Arquebus should also have a much higher damage per shot, making it preferable for fighting more dangerous foes like Bears, Drifters and Bosses.

I think a Matchlock Arquebus would fit the game well, they were more powerful, accurate and user-friendly than the hand-cannon so they can be a big upgrade over bows, but are still low-tech enough to fit the games medieval/early Renaissance aesthetic.