The graph is particularly interesting, because it shows that having between 0.5 and 2.5 pips in shields is nearly useless. If you've got 2 pips in shields, just put that energy into weapons or engines where it might make a difference, because there's almost no difference between 0 and 2 pips in shields. (sure, if you need to recharge damaged shields, 2 pips can help, but then you're probably better off briefly using 4 pips to charge your capacitor again, then going back to spending your energy in a way that makes sense.)
It's no wonder many people have complaints about this game. Being complex is, in itself, not a big issue. There have been good games in the past (like, say, Jane's F/A-18 or Falcon 4.0) that were far more complicated. But those were based on real systems, complex machines of war that had real engineer teams working on them, trying to make those machines as effective as they could be, and as user-friendly as they could be made without compromising their capabilities. Difficult games, to be sure, but the difficulties made sense, and the manuals made a good effort to educate the user about military tactics, all the possible systems, they told you about the attack patterns the systems were optimised for,...
Elite is complex too, but too much of it seems to be arbitrary, capricious, magic complexity that makes no sense and isn't documented. Systems should make sense. Or, if some balance reason dictates that this isn't possible, at least make sure the users don't have to hunt through the forums for a month to assemble the information that should have been in the manual to begin with.
No, what's in the manual isn't enough. It just says more pips to shields strengthen the shield, but not by how much. Someone reading the manual might get the false impression that 2 pips is a good compromise setting, but in reality 2 pips is simply rubbish and almost as bad as 0. If you're going to include a thing that doesn't make sense like that, the exact numbers, or a graph like the one above, need to be in that manual.
In my opinion, if you feel including power distributor management is needed at all, the shield systems in games like X-wing, TIE fighter, and Wing Commander: Privateer made far more sense than the ones here. Power to shields simply determined the level of shields you could maintain. Full power to shields gave you fully charged shields. Drop the power, and you'd get lower shield charge. Translated to E

, that would mean lower shield charge settings would only give you 2 or 1 ring of shields.
Though it would probably make more sense not to have power distributor management at all. That's such a world war 2 era thing to do, manually managing prop pitch and engine mixture settings... In modern military planes, all of that stuff gets managed by the engine computers, allowing the single pilot to keep his attention to stuff that matters more, like the tactical situation and data from the many, many sensor systems his aircraft carries.