aaaa stop making me write an essay on random stuff on Smogon i need to grind more in Ragnarok Online :(
The reason I didn't provide arguments is because I just stated definitions, which is in the end, what we are arguing. I'll first start by rephrasing my definition. Secondly, sorry for being an economist ;)
First, we all have constraints. This constraint means that we are not omnipotent, of course, and there'd be no point of studying anything. These constraints are physical laws, any external conditions you may set on yourself (or other people may set on you), etcetera. We make our decisions with regards to our constraints.
Our initial decisions are defined by such constraints. For example, I will be foolish to jump off a cliff, because I know that I cannot fly. Even if I would wish to try and fly, I will avoid this. I will quickly learn my hand burns in a fire, and will stop being as close to it as I used to be, etc. As we get new information, we adjust our values - we learn these constraints, and try not to break them. Hence, the existences of such constraints due to physical laws are quite obvious. We define stupidity as an attempt to break constraints that are there (note that logic is often a constraint that we put on ourselves, and in a discussion, it is literally a physical constraint)
Meanwhile, we have constraints such as the fact that I'm not a great singer. These again, affect our decisions - but in the end, they're just constraints - equations. The more time I invest in singing, the better singer I'll be, but because I am a poor singer, I have to invest quite a bit of time into it, and I measure this. We make our decisions based on such constraints.
But, in order to make decisions, we need values. In the economic sense, we have this vague concept called "utility" that we attempt to maximize (but it's too vague to be an actual value since it's sorta all encompassing) we try to maximize profits, minimize costs, etcetera. We hold these values, and we make decisions based on these values.
But there are externalities, or evil. As we maximize profits, we have unforeseen effects in the world that we simply do not care for or account for. Whether this is pollution, murder, or second-hand smoking, we don't care about the "bad" effects as such we go on with our decisions.
Hence, given perfect information, such evil no longer exists. You know which value you must consider for wellbeing, and you know every effect every action will do and how it will work out. You know which values are important, and you hold yourself to it. You will not simply just kill another person in such a state for pleasure or because you are angry and what not, since under perfect information, first, you are wise and you will control your emotions, second, you know the exact consequences of it, and hence you're not just going to kill people, since you know that killing one person does have an effect. No evil is possible in such a state, because you hold yourself to the "absolute" value (I know that you know that I believe in such a concept, if you don't, then that's that - in the end, it's just a difference in what we believe leading to different conclusion. I have justified my belief for an absolute value in previous engagements so I don't feel as if I need to do so again). Such actions may seem evil in our eyes - simply because we don't understand, we can't see the "absolute" value that the being holds itself to.
Because we do not have such perfect information, then free will is a consequence thereof, and evil is a direct effect of free will. We make our own values, and we hold ourselves to it. These values are "gods", something that we center our lives around. This ability to choose our own values is a direct consequence of eating the fruit in Genesis - you now "know" good and evil because you self define it, and you have become the judge of the world.
Hence, I don't believe that you can simply just "constrain" evil, as you have said. It is not plausible, since evil is simply a result of free will - removing evil can only result from removal of free will, meaning that all our actions are simply plotted out in advance. I'm not going to say inefficiency in the definition I have defined is evil, but the negative effects. Suppose that we are indeed all immortal - but we are able to communicate. So I decide to spend all eternity bombarding you with Pokemon talk and continue to go after you. Okay, so you're going to say "Let's make that impossible", so in which case, I'll just throw stuff at you, and so you make that impossible. Okay. Now let's say that miscommunication has damaged you, so you say, okay, let's make that impossible, so you either have perfect communication, or remove communication (at which point "what's the point of existence"). Now suppose we have perfect communication, then at which point, we all know which kind of values everyone takes into consideration, and at which point, it's just as good as perfect information. You know what to do in every case, every action, etc. Physical laws don't bind you since you're immortal and you transcend it (you have to remove accidents too, so you can float, fly, you aren't affected by temperatures, you are impenetrable, you don't have to breathe, eat, or drink), so at that point, you're literally a god. It's not free will at this point - there are no values to consider, only the "absolute" value, or something very very close to it.
As long as we are able to make our values to decide under constraints, evil follows. Hence my statements that I have made (which weren't arguments so I apologize if you thought they were).There is really, no other option. Evil is also relative (do I really need to back this up... this is obvious), so what may seem to be evil to one is not evil to another - so even if a "perfectly rational being" may do something that may seem evil to us, it's not, and cannot be. This is the point of the genesis story - that through this disobedience to God and the "absolute value", we rejected it, and made our own system, and now we are the ones who decide what is right or wrong and good and evil. Removing evil from this world would also amount to removing our ability to make such a decision, meaning it removes the ability to choose our own values. The point is this - if a "perfectly rational being" is making decisions, how can it be evil? It may seem evil to us, but remember, we work with imperfect information, we work with our biases, we work with many many other things simply because of the fact that we can't consider every side, every fact, or know every fact (yet). But I'd be wary of calling God "flawed" and try to gather more information before hand.
I hope this suffices and it's not just a non sequitiur ;)