Virtue Ion is right, a QEV will DRAMATICLY improve efficeincy as well as shot-to-shot consistency. There are a variety of mods available for the Ion-firing cans/bolts/end caps, etc...
A good buy as well would be any of the aftermarket bolts available. They will all give you more shots per tank and better consistency over the chrono.
Also about the banjo fittings-BE CAREFUL HOW YOU SCREW THEM IN, DO NOT CROSS-THREAD THEM!!!! Once that happens, it can be difficult to get them re-tapped correctly. Check for excessive wear on the threads, that may explain your inside leak.