At the time, the only downside to the Syringe Gun was 'no critical hits', and since the other guns didn't have crits either making both was useless. Now the HP regeneration change is more useful in TF2, but in Blockland most people would only pick the 'battle medic' option anyway and the regeneration is unnoticable without a health bar.
For the Grenade Launcher I felt that the current system (4 pipes out at a time) limits spam enough and rewards direct hits with less delays.
