So, again, the sentence is
and the provided English is
Just think about it.
I don't understand quite anything about the sentence. I know of the てみる structure but I don't really think it is related. If it was just 「考えてもいい」 it would make sense, even though the English version is (I think) more "assertive".
It turns out that the use of verb + がいい is a form of commanding or invitation, as was suggested in the comments, and explained at The meaning of ～がいい
With this in mind, I found a discussion about what I think is an equivalent expression on yahoo:
Here the answer describes the meaning of the phrase as follows:
So I think I understand that this is an invitation to think about something, with the implied nuance that doing so may prove to be beneficial/useful, but I still don't understand how this stems from the usage of 〜ても〜