[Wombat]

Ok, my sj51/g16b efi has just come back from suzistore going through and fixing a few issues, they sank about 50 hours into it to sort out a no start issue and I picked it up earlier today they have done a great job fixing my primary issue and several other future issues, however I am left with the remaining issue of when it's cranking over it sounds horrendous, sometimes its fine, sometimes it's just spinning and not engaging, sometimes it's...terrible. I had replaced the starter with a slimline one back in September shortly before the car went to them in October.
The have had the harness out multiple times and it has been redone as a lot of wiring had been burnt from overloading and fixed all the issues with it, gone over all the grounds multiple times and tested the battery etc, they tried a new starter motor also and tried a 2nd hand one they ground down which is currently in it as that was as good as they could get it to start. They replaced the ring gear and that didn't solve the issue so they pulled the gearbox again to inspect it etc. The timing and clearances have been checked x3 and fine.
They suspect I have too much compression (195psi) which may be causing the issue but the engine has done about 30***km since getting a ground up rebuild and it hadn't been an issue until recently , I don't doubt that it is potentially contributing. They suggested trying a hi torque starter so if there are any recommendations for one that would be great.
They have covered pretty much everything my cavewoman brain would have checked so before I start pulling the car apart and throwing even more $$$ at it and pulling my hair out what are some other things can I can check?
She drives really nice once I can get it going and I just want to be able to turn the key and enjoy it.
Thankyou in advance.