I use 8.5:1 as a maximum dynamic CR and only if the ignition advance is programable.
For a dissy engine 8.2 is about the maximum .

Ceramic coating works. Be careful about the quality of any coating you get done though. Cheaper is not always the same quality. I spend around $400 on each four cylinder engine I get coated, and a further $160 on the exhaust headers inside and out.

Its interesting to see that most V8 supercar teams and top doorslammer and rail drag teams use ceramic insulation on chambers, valves and pistons. Some have been using it for 15 years.

HRT replace the bottom end on thier cars after 5000 race Km's and the pistons mostly show no appreciable wear after this distance.

Cooler engines and lower thermal stress on rings (allowing lower ring tensions) are the biggest benefits to performance and reliability.

Engine Analyser Pro v 3.3 is the only one I have seen worth putting any effort into. It takes account of bearing friction ring type and number and lots more. It takes a while to setup but produces good base data to compare likely effects. It is not going to give hard output nmbers but makes a good comparative tool.