Max out bonus by repeatedly shooting up top and then work on doubling bonus by hitting the A B C D drop targets. Bonus is really the only meaningful scoring feature.
Full plunge to get maximum hits to rollovers and switches in the top
Bonus is the only scoring that matters
Advance bonus with every 5 spinner spins, scoring drop targets, or making the top advance bonus rollovers
Base bonus max is 15K and can be doubled by completing the A B C D drop targets