FWIW, I would describe the original C1 as a Victor action (skinny barrel, no safety, flat-faced rear receiver plug) with shortened barrel, full-strength Vulcan spring, and a new stock.
The second-generation C1 was, IIRC, identical save for the addition of the safety.
The third-generation C1 picked up other changes from the “Mk 3” Vulcan family: a heavier barrel, and as mentioned above a wider, ribbed, curved trigger blade whose center is a bit further aft - and beautifully illustrated below by louisvanhovell’s photos.
As Geezer mentioned, the stock wrist angle of the C1 is very flat and quite uncomfortable for many, me included. The lack of drop at the butt heel does a great job of controlling muzzle lift in this light and powerful little rifle, and I found it very easy to shoot well in spite of the pain! . The late trigger gives a more comfortable hand position, and I like the balance of the meatier barrel, too.
Beeman’s catalogs claimed the design inspiration was the old “western” lever-action carbines, like the classic Winchester 94. Where they went off with the C1, is that those guns had a lot more drop at the butt, making the wrist angle more comfortable.
I always admired the gorgeous metal finish and crisp woodwork on Webley rifles of that era, though. To my mind the trigger isn’t even all that bad once you break it in, lube it a bit, and explain to yourself this is a dedicated outdoor sporter, not a target rifle, LOL...