So the reliability concerns are really a matter of poor design? I was under the impression that the design was solid, just the execution was sub standard.
Bad shuttle valves, broken solder joints, undersized cooling systems and a ridiculous external thermostat etc are design issues. Slipping liners, porous blocks, misdrilled blocks that eat front covers and oil pumps are execution issues.
All are manageable in one way or another, but a refresh isn't going to cover them all.