IMHO the meaning is something like “as you see fit”, but it’s vague, as よう is vague in general. Grammatically, I think the only possible parse is いい (good) + よう + に (adverbial copula). よう has two basic (and sometimes indistinguishable) meanings: as ~, and so that (it is as) ~. Thus, “in a way that is fine (with you)”, “so as to agree with what is fine with you”, or “so that it is good (for you)”, but since what is いい is implicit, the expression remains equivocal.
Off-topic
Well, I just wanted to point out that we shouldn’t automatically assume that people who read translations don’t read a lot or, to put it bluntly, are somehow “less educated”, at least w.r.t. languages. 
I was going to digress further into reminiscences, but I’ll settle for a simpler explanation: I think, quite plainly, that… I have better tastes in French?
More seriously, I feel that my appreciation of the language is quite a bit superior when reading in French than it is when reading in any other language, including English. My sense of what is good prose, beautiful style, is better, or at least better-defined (since whether others would agree with my judgement is probably a matter of taste). So, even if the translation is subpar (and there are subpar translations in French as there are in other languages, assuredly)… at least I would better feel how subpar it is. 
As regards translations, well, maybe if indeed your reading history is very skewed towards English, as seems to be your case. Otherwise, I’d think that the native speaker advantage would just give you an overwhelming headstart in judging whether the resulting prose sounds good or not.
Anyway, this as well is just my opinion.
Yes, in fact some linguists are starting to wonder if it will become standard at some point, being reinterpreted as a bound conjugation てる in the same way てあり contracted to たり and then to た.



do use the vocab sheet!
