Is there any reason to use another weapon and not a steel sword

Solution 1:

Steel swords have enhancement slots for runes, while the additional weapons do not. This can mean up to 21% additional damage + critical effects on top of whatever the sword innately has.

Additionally, as you get farther into the game, the steel sword damage will continue to increase upwards, whereas the additional weapons simply stop appearing at all later on (meaning if you want to use a 12-18 damage Guisarme in act 1, you're only doing a third of the steel sword damage you could be doing in act 3).

Solution 2:

So the Witcher is largely designed to use swords (Steel and Silver), but as you point out there are a couple of options:

• Swords
• Ranged
• Everything else

Now I assume you're not concerned with the Ranged ones, so let's talk about that everything else category. These weapons frequently have % Stun and % Knock down, both of which are useful traits as they allow Coup de grâce (what I assume you mean by chain attacks). However, the flipside is that they tend not to be as strong as many Steel Swords. Additionally, you can't use any of the Sword Enhancements on them.

While these common weapons can be very useful early in the game, ultimately enemy damage reduction gets too high and Steel Swords get too strong not to use them.

Solution 3:

So, there's one notable exception to the answers posted here:

The Operator's Staff, available in Chapter 3, is a viable alternative to endgame Steel Swords, and is arguably better than all of them for some Witcher builds. It offers an extremely high chance of Incineration, as well as Stun and Freeze procs, so a build with high +Critical Effects chances (possibly through carefully planned Mutagen stacking, though not needed), can reliably Incinerate or Freeze just about anyone you hit.Meanwhile, the base damage is comparable to a fully rune loaded Forgotten Vran Sword or Caerme. You sacrifice very little on that front.

However, unlike a standard Steel Sword, the Operator's Staff has an unorthodox swing animation - it has an extremely long reach and wide arc, which makes it very useful in some of the large scale brawls that characterize the end of Chapter 3, but it does take some getting used to. Finally, when carried, the Staff generates a bright light - handy for exploring some darker tunnels without a Cat potion or similar.

The downside is that since the Staff is not a Sword, but rather an 'Additional Weapon', Geralt is not his usual acrobatic self when wielding it - specifically, Quick Attacks will not have Geralt leaping to his target or bouncing around the battlefield like a ping pong ball. You'll need to be much more conscious and in control of your positioning.