I reply with a selfish dint, as I am new to C&S, and more openly, fairly new to being a GM. So likely this reply is more soliloquy than sagacity. I own both ICRPG and C&S, but have only played C&S.
Subjectively, it seems that ICRP loot tables will take a bit of conversion. Please hear me out. I say this because anything involving a bonus to the 6 core stats in ICRPG will translate to C&S only through the GM’s interpretation of those bonuses at specific times and circumstances. It will be easier for an experienced GM.
Currency is further abstracted in C&S, and thus any coinage as loot will have to be changed to some other form of loot or simply turned into Hero Points, though this arguably reduces what some view as fiddly bookkeeping. Some RPG systems do this in opposite fashion and say gold is experience.
Healing is scaled drastically different for C&S. e.g. in ICRPG a “shabby loot” of soldier’s rations heals 1D4, but in C&S a full rest in safety grants 1D4 healing!
Lastly, bonuses to effort and armor would have to be thoughtfully assessed to truly estimate their impact. C&S mechanically funnels combat into a single roll and rightly relies on narrative scaffolding.
Because Hank has slowly matured his concepts of efficiency, we see each subsystem taking a “pass in review” to how it both integrates and drives the pacing of play. I see C&S as a rules-light system that seeks to get out of the way of role-playing storytelling.
Practically speaking, if you spent a good deal on ICRPG, I would play that for a good while before moving on. But personally, there is a reason I am playing C&S over anything else. The innovation.
Perhaps the ease with which any game system can assimilate converted material is reciprocal to its originality of mechanics introduced into the industry space.