I would try a 10-5 prop to replace the 10-6 to raise the RPM and make a bit more power. Often not much difference in speed due to the rpm increase.

Irvines are BB. This is a good thing IF you keep the bearing clean. If you are still taking a bunch of dirt baths with the front end of the airplane, then the plain bearings are hard to beat (much easier to clean).

I've seen plenty of good running LA engines. They like fuel with a bit more oil. Their timing is a bit on the mild side, so they are easy to start, and idle well at the loss of a bit of top end power. Traditionally OS engines were timed this way and Super Tigre were a bit more aggressive. But today, companies like OS have engines all over the tuning spectrum to give a bit of product differentation between their engine lines.