I also think that the snipers' scoring is fine the way it is, killing free units on the battlefield almost always means nothing. Now kill a premium unit and you've done something, helped save a few teammates, which you do get good points for.Engys should get more points, especially for repairing tanks at the frontline as its a dangerous place to be an infantry unit. They should also get more points for disarming C-4 and beacons. Maybe they should even get more points for a kill due to the difficulty of this with a pistol.
I find that when I'm a hotwire or tech I'm sacrificing score and ladder big time but the team win is most important so when nobody else wants to defend then I have to. You can rack up big points on the no AGT/Ob. maps as these units however.
Victor