If you're anything like me, and according to your scores, you are, but better.
You probably may never make it further. Sorry, but since we perform similarly, maybe you'll just repeat me. Look, we do similarly as bad on Low Rider, yet both do well on Lasso and Foolin'. You can actually score on Walking on the Sun and Werewolves of London, so you're not doing too bad.
Probably the most useful tip I can offer is to use the comfortable high range you can hit, then go higher for the low notes. It seems to work more often.
At this point, just try and have fun and forget score. 2 or 3 problem songs is nothing compared to your catalog.