Part upgrading (ie the increments in improvements)

[SunJumper]

I'm curious about the upgrading system that might come about in the future, in career mode. There seems to be four methods to calculating how the parts will improve (costing "science" and "currency").

1. Linear improvements
   
2. Improvements where the value asymptotically approaches a value
   
3. Linear improvements to a point, and then asymptotic improvements
   
4. Manually implemented improvements for each part type
   

Clearly each example has pros and cons, for example 1,3, and 4 allows for naming of individual upgrades (for immersion), but number two (or three), seems more realistic. Perhaps each improvement should be x% more than the last.

For convenience, I have listed potentially improvable quantities for the part types:

All parts:

• Mass (decrement)
  
• Heat resistance (increment)
  
• Crash Tolerance (increment)
  
• Maximum torque before breaking (increment)
  
• Drag coefficient (decrement)
  

Engines:

• Thrust (increment)
  
• Isp (increment)
  

Ion engine specifically:

• Electricity consumption (decrement)
  

Fuel Tanks:

• Fuel Capacity (increment)
  

Command pods/Probe cores:

• Electrical capacity (increment)
  
• Power consumption (decrement)
  
• Torque efficiency (increment)
  

Electrical generating systems:

• Efficiency (increment, but max of less than 100%)
  

[Capt Snuggler]

It would be cool and more difficult if there where trade offs. if you increase the impact tolerance it will increase the Mass.

ether way, great idea!