I wonder if he just used some of his previous sculpts for inspiration
Yes he did.
Most (though not all) of the Copplestone FW range have a clear 'progenitor' figure in the range he sculpted for Grenadier, now carried by EM4. In one or two cases the figures are almost identical. In most cases, you can see how he evolved the figure to its mark II state.
For the most part, as you'd expect, the later 'own brand' figures are a slight improvement over the Grenadier / EM4 originals. Not quite as willowy. Obviously the artist has honed his technique in the intervening years, and has taken his second chance to achieve exactly the look he wanted first time round.
That said, there are a few of the original range that I prefer to the later FW versions (like the female cop with the SMG), and there are a few types in the original range (like the security guards for instance) which he never remade for his own FW range. Which is odd, because those are the EM4 figures I see used most often.
He never remade savages for FW either. Maybe he knew from Grenadier that these didn't sell very well. Or maybe he's still getting round to it!
The big problem, of course, with the original Grenadier / EM4 range is that they have crappy horrible tacky slotta bases. Ugh!
