Very nice guide you made. I would like to give you a few tips as to what I do.(not sure if some one already posted these)
1. At the start of the match you should be a tactician with the assaults second badge so you can run straight to the good spawn points in the map very early and dominate after that.
2. I disagree with the whole thing about a medic being behind the front line. Whenever I play as medic, I'm always the one that revives someone in the front lines and by placing a few C4 at a possible flanking position that the enemy can come through helps a lot.
3. If your ever a sniper and happen to find a shotgun, PICK IT UP. If you do then u turn into an invisible ninja with a shotgun. What you do is you wait in a corner were the enemy comes through often and then blow the away.
4. As a saboteur, you stay behind enemy lines and take them out when they spawn. If you are a leader of a squad then your squad mates will spawn on you and help out.
There are my tips. Hope you enjoyed them.
You may get called a noob for doing what is best for your team and helping them win