A while back I tried out the very intriguing division led by prince Boguslaw Radziwill published by Wargamer.pl in PDF format. The division has a base of Lithuanian/Commonwealth troops, but can field Swedish allied regiments as add-on regiments. Imo you can play this army as a Lithuanian army loyal to the commonwealth – or when playing with the add-on Swedish forces play it as the traitor army that fought against the Crown with the invading Swedes during the Deluge.
For a Commonwealth army this force has few typical commonwealth troops in it. Instead it relies mostly on western type troops. However, the cavalry regiment of prince Radziwill includes a hard hitting combination of cossack style cavalry, elite Pancerni, two bases of winged hussars and Reiters. This alone, and especially when playing the base of the division with only 3 regiments, gives you a nice mix of potent cavalry units to go with static and mobile infantry formations.
The army suffers from a couple of drawbacks, such as the Commonwealth special rule of "Treasury problems", but more importantly your commander is hated by his troops and before you start the battle you must roll on a chart and check the mindset of the army. The results range from no effect, to a single or all regiments except prince Radziwills own cavalry regiment be "insubordinate" and very hard to control.
The prince however does aid your army with a pretty good rule, "Stern", which gives every regiment in your army +1 to their breaking point threshold. This is a welcome bonus, especially if you have small regiments such as the dragoons.
To conclude, I had a great time playing this army, and hope to field it again soon with Swedish allies.
Check the full AAR along with some 50+ pictures over at my blog:
link
of 
