SorryImJustDiamond
Does MC plan to introduce Tech at an accelerated but mostly chronological rate from our universe until he reaches modern-day around his death? he could probably stall, so they have Korean war era military tech by then and stay ahead, but when it comes to other fields like improving crops and livestock, all medical advances and science he needn't hold back right. Then, leave some weapon designs behind for the new emperors eyes only that can be introduced as needed?
SLR...well in terms of the introduction of technology, he is taking it slow, like let his scientist and engineers study the concept before going over to another technology, so that way, they won't just rely on the "luck" of mc. But to reach the level similar to the 21st century? Well I don't think...maybe cold war era tech