I propose to be introduced some research or connected to existing Detection technology, all the planets within a certain radius of colonized planet already become visible and not showing them with "?"
This in order to not have colonization and then leaving planetie - a waste of time and resources

Not desirable. If you are talking about free fields, the major reason for recolonizing, these are determined randomly during colonization.
It would be wrong to be predetermined and known before hand, since all older players would get the prime cuts and leave the scrap for the new ones;(

Galactus, To see what kind of planet

This resource-intensive for the server. Each planet - a record in database. Each "question" - is lack of record.