I may not have the prettiest voice but I am a capable singer.
My highest in easy was Hoobastank - The reason, 9970 points (and there were witnesses).
In all fairness it used to be my brother's song so I rehearsed the crap out of it so I could beat his score. I know the song really well and I sing it a lot (my brother passed away so I sing this song that he liked from time to time).
I can do 9000+ in medium as well for many songs, especially English. In fact, as a songmaker, I use 9000medium as a reference point. If I can do 9000 or more on the song I know its ready to be released on the forum
For people who have lower scores and want to up their scores I suggest two things:
-buy a decent mircophone (I have 4 I use to test out new songs. A microphone that will not go up and down on a realy long note can make a lot of difference in the points!