Complicated, Fading, and California King Bed are the ballads more than likely.
S&M, Man Down, Raining Men look like the uptempos.
Cheers, Skin, Love The Way You Lie (Part II) as midtempos?
There is no way in hell, Ri-ri isn't doing re-release, the demand for more songs is too high. WTC will probably be a bonus on the album, if bought from iTunes.
Her album has a PLC, a product life cycle and businesses like Rihanna's record label will think of ways to prolong the life cycle; which is done by re-releasing the album with new songs. There will probably be like 5 new songs to make 16.
Skins and LTWUL (Part 2) are probably mid's. Cheers is an up-tempo; she said it's a dancey song. This could end up being better than Rated R and might be as good as GGGB.