Ignition system

What do you mean, "improve"?

Improve on cold stars without modules such as quick start.

With a high compression ratio and gearbox I have never seen or heard of any way to do so on this engine and anything that was done would most likely be illegal in most countries.

Plus as many over the years have found out if you change the way Rotax runs the engine they trash their engine and that usually cost thousands of dollars or a new engine. I have pictures as does Rotax service centers of people that thought they new more than Rotax and spent a fortune fixing their engine. It runs fine and has a good reliable history just like it is. Yes Rotax has made some improvements over the years, but it's because they have the correct test equipment and engineers to do so. I would bet over the decades they've had their own issues during testing.

Better to let sleeping dogs lie at times. :) Cheaper too.