When I think of an example in rap that personifies braggadocio, I immediately think of the song "3 Peat" by Lil Wayne off of his album Tha Carter III. The entire song's theme is ridiculous and over-the-top arrogance because Lil Wayne believes that this album will be as great as his first two, which would give him three straight record-breaking albums.
Besides the fact that the name of the song is braggadocio in itself, the lyrics go beyond that by saying he himself is the best rapper. In particular, when he states:
"Get on my level? you can't get on my level
You would need a space shuttle or a ladder that's forever"
Lil Wayne goes on to mention himself as the best and as being on another level than other rappers throughout the song, but, to me, its not just the lyrics that make this song great, it's the pace and the rhymes too. Lil Wayne paces the song very well because the lyrics and rhymes push the song forward so that it sounds like he is rapping for the entire song. His rhymes are a key part of why the song flows so well. There are no choruses or instrumental sections; "3 Peat" is a track with just rap verses.
I believe that "3 Peat" is a good way to open an album because it displays Lil Wayne's ability to rap creative and rhythmic lines. I also feel that since the track is all rap verses with no choruses the song easily transitions to the next song in the album.
Overall, I think that "3 Peat" by Lil Wayne is a great example of braggadocio in rap, and also that it is the perfect song considering its position in Tha Carter III.