The number one issue is headgear, and if you weren't feeling particularly energetic, you could probably just deal with that and call it a day. The original miniatures have bare heads with a fringe of hair. It looks like typical male-pattern baldness, but the idea is that you attach either the wide-brimmed hats or the forage caps (both are included in the kit) to determine whether your troops are Confederates or Winners. For our purpose, it's quite easy just to greenstuff a fur-lined Cossack cap over their heads instead. You can even use the hair fringe as the back part of the fur lining.
For variety, one of the riders is hatless. I cut off the hair fringe, and sculpted the traditional Cossack forelock on his scalp. Only slightly more work than the hats, and very distinctive. Which reminds me, only about half the riders are sculpted with mustaches, so you'll want to fix the rest of those.
I want my half-hearted historical accuracy to at least continue past the models' heads, so I extended some of the coats a bit. I sculpted the coat extensions before attaching the riders to the horses, which is a bad idea, since the greenstuff can easily end up conflicting with the canteens and bedrolls and such on the steeds. The ones without long coats are supposed to be in their shirts, though maybe I should trim off the buttons on the one. Also, one of them has had baggy pants added.
Weapons! The kit comes with enough swords for every rider, although the basket-hilts are not ideal for Cossacks (at least not in my era, Napoleonic-era Cossacks maybe different?). There are also revolvers, but those go straight into my bits box, obviously having no place in the 1600s. Finally, the box contains three banner-poles and matching arms, which could be used as lances in a pinch. For my lancers, though, I used Wargames Factory plastic bits - Persian infantry right arms and WSS infantry pikes.
A word on the horses - they are not small. I considered mounting these guys on smaller spare Wargames Factory or Warlord Games horses, but then I decided that the stowage sculpted onto these horses made more sense for Cossacks than any of the other cavalry at Berestechko. I'll just have to pretend they don't tower over the pancerny and hussars...
I think my next post here will be a size comparison of the various WGF, WG and GW horses I have on hand.