Suzuki would likely have a higher OPS than he does now if he played as infrequently as Susac. That's the rub with catchers, probably not wise to take their OPS over a small sample and assume they can keep it up over the rigors of catching a full season. So yes, you are making assumptions about Susac and his ability to continue hitting, while catching a much larger workload, that I would not be close to accepting. He has caught only 11 full games so far this year (for comparison, Suzuki has already caught 37). Probably the most underrated aspect of Suzuki by people who look solely at his numbers is his ability to catch almost every day. Not many catchers can do that and few, if any, that would be available in trade.