In my opinion, the primary issue concerning science in KSP1 is the limited size of the tech tree. After a certain stage, you accumulate a significant amount of science without a clear direction for its utilization. A valuable enhancement could involve implementing a small tech tree for individual parts, each offering enhancements to specific characteristics. For example, consider an engine upgrade that requires a certain amount of science investment and provides benefits like a 2% increase in thrust or a reduction in weight, and so on.