The small stats are correlating stats to the bigger stats that they’re connected to. Please see the HUD Layout PDF to see what exactly they mean.
If you have a hard time reading the small stat numbers, do not worry too much. Mainly what you need to see is the color of these small stats. These colors tell us quickly if the stat is low, average, or high, so we can proceed with our decision. If you would like to have the stat appear more readable though, you may want to try a larger HUD size, or customize the HUD yourself by changing the font for the statistics which are too small for you in HM2 -> HUD Settings -> Stat Appearance.