I don’t really understand the reason for the 60 gal conventional tank. They are sometimes used for aeration of smelly water or as a settling tank for sand and solids. As long as it is after the CSV it won’t hurt anything. If there is no an air maker system on it, the tank will eventually waterlog and not give any drawdown, but the 4.8 gal tank will still make everything work OK. If there is an air maker system on the conventional tank, it will add to the draw down from the 4.8 gal tank, which can be a good thing.
Shouldn’t affect the flow rate or lifespan much either. Your well company is smart enough to be using Cycle Stop Valves, so they must know what they are doing.