I agree His dealings do seem to centre here. The Bible tells us the world is held in reserve for judgement by fire and that the cosmos as it is will pass away and a new universe will be created. There is no mention of physical life anywhere else. Maybe there is but there is no mention of it in the Word. Life out there somewhere is not mandated simply because there’s so much room.
There are many things that are not in the Bible. As many Bible scholars have said, the Bible is "need to know."
Consider this (John 21:25):
And there are also many other things which Jesus did, the which, if they should be written every one, I suppose that even the world itself could not contain the books that should be written.
There is no mention of molecules, magnetic fields, inertia, and the electromagnetic spectrum either. Using your logic, none of those exist.