To be honest you need to have more experience playing Brink. The fact that you admit to only recently getting a character to level 20 is actually a bad thing. It is not uncommon for players to have 5+ level 20 character at this point so your opinion is based on a very limited amount of experience.
Was your character a Light, Medium or Heavy? Have you even spent extensive time playing as the other body types? Which weapons did you use and how much time did you spend using them? The fact that you feel the pistols need more ammo is bad enough but then to use the in-game stats, which are entirely wrong by the way, only proves your lack of experience with Brink.
Add in the comments about there not being increased headhsot damage against downed foes, which there is, and I question if you ever did any testing on these ideas at all or simply guessed for most of them based on your ‘experience’. Not all of your ideas are horrible but most of them simply demonstrate your limited viewpoint of Brink’s gameplay.

If it’s already there then no need to change it but I still keep my word for the rest of my ideas.