How was the third game in this series?
Hell, any big fans want to rank the series? I'm interested in this (even with a 30fps cap) but I've only ever dabbled in the first game.
This is all from memory, I haven't played WotS1-3 in a good while, so I'll just post various thoughts of what I can remember, since you've played the first game you have an idea of how it goes and maybe someone else will find it useful. All the games are best summarised as a small scale samurai sandbox meets a CYOA story. The true ending for each game requires many playthroughs to understand the flow of events and manipulate the outcome toward a favourable conclusion (this generally involves getting the various factions to stop fighting each other and face the true threat).
WotS1 is probably still the best, just because it has an insane amount of branching and they do most of their "cutscenes" in a unique way (conversation progresses automatically, you can walk around, act as normal), which allowed the player to talk/interrupt/strike any of the NPCs during particular scenes. Although this might seem like a minor detail, this mechanic can lead to some unique situations where you can pull off double crosses and the like. The game played out over the course of 2 days and the story itself was tightly controlled but this afforded it the widest array of meaningful branches in the series imo - the number of different ways the first area can play out with the attempted kidnapping is something to behold and none of the sequels match it this regard. Combat was also superior to WotS2 & 3 in terms of player skill. Features the least wacky elements of the series by far.
WotS2, sadly was a bit of a case of dumbing things down in terms of combat. The satisfying push/pull combat mechanics of the first game to weight your strikes were disposed of and a much easier (and easily abusable) parrying system was put in its place. A new "fencing" style was added which was pretty cool (carried through to later games). Most (maybe all) the environments were perfectly flat planes which was a bizarre step back from the first game. The wackiness started to creep in a bit more with this entry in terms of player customisation and a terribad english dub. There were 3 factions and the game played out over a period of 10 days and featured considerably more endings than the first game. Generally speaking, the game sort of drifted/meandered in a strange direction compared to the first but I still had a lot of fun playing it and if nothing else, some people prefer the fact that WotS2 doesn't have the strict time limit of the first game, there's a lot more scope for just messing around in Amahara in this game. Most notably, the ability to interject/interrupt/be an ass mid-cutscene was scoped back considerably so the story elements are more on the rails and feel less organic. WotS1 is somewhat unique in this respect and none of the sequels have ever really recaptured it (likely due to larger game world and overall increased scope).
WotS3, the ability to draw your sword mid-conversation came back, unlike WotS1, this is always perceived as a hostile action and NPCs won't (as I recall) give you a chance to back down. Basically the implementation is a bit meh. Since progress isn't tied into time (game can potentially be played endlessly) it can get repetitive. Weakest overall faction leaders in the series, they don't have much presence. Combat was moved back to be closer to WotS1 but if memory serves, this was the one where they removed the ability to crawl if were knocked off your feet, so in terms of combat it didn't quite match the first game, they added a new "instant kill" mechanic which pretty much became this game's combat gimmick. Factions were okay as I recall. They added a partner system as I recall so you can have an ally who will help you out and maybe move into your player home if they liked you enough. WotS3 Plus extended this to some of the story NPCs but of course, we didn't get that version. Again, for me, it was a good game but it didn't scratch the same itch as the first title did. This was the one with the skirt/kimono cutting mechanic iirc, so the zany factor was still present and accounted for.
WotS4 blends the best parts of the first and second games. It brought back the depth of combat from the first game, mixed it in with a good town to explore and plenty of interesting characters and events to discover. Health is handled differently in WotS4 and as such its significantly more difficult to become an unstoppable killing machine since they capped the max health much lower. This actually worked to retain my interest a lot more on subsequent playthroughs, in earlier games, you could just pump up your life points and play through sloppilly, that's not an option here. I believe it's set in the same town as the 2nd game, but obviously things have changed. Basically WotS4 is the best entry overall and the most content-rich however WotS1's story and branching has it beat in that domain due to smaller scope and less wacky nonsense going on, but don't let that put you off as 4 has a lot more content to compensate.
So:
1=4>3>2
The first and fourth games definitely encapsulate the best elements of the series imo. They're all worth playing though, the whole series is overlooked due to the shoddy graphics but it's really easy to sink a significant number of hours into any game in the series. Hopefully the Steam release will bring it some of the recognition it deserves.