I'll start with a word I learned today!
This word, which means keen insight or acumen, translates perfectly the word بصيرة /ba,ʂi:ra/ which is often translated insight.
My vote is that this word is more likely to be alien to most readers. While "insight" is an understatement, acumen may be about right.
I think my vote is also that the uncommon word should be avoided. The reader will probably have to use a dictionary if we use the uncommon word, and that defies the purpose.
As for بصيرة, I think 'vision' might also work. I feel that eyesight has taken over from vision when it comes to literal seeing, and now 'vision' by itself stands for insight/wisdom, etc.