Alcoholic_Panda
MC could recreate the magic of the anime Mahouka Koukou no Rettousei, and also try to use hand signs like Dr Strange, since this is also a language. of equipment it would be interesting for him to create a reactor and use a philosopher's stone or part of it to convert the energy into magic and ki or touki, he could also create a kind of magical internet for supernatural humans since there is one for demons, and would use it to sell its various products, from household appliances to food and drinks made from genetically and magically enhanced materials and plants. and using this Internet he could collect energy through the intentions and emotions of users like the gods with faith, it would be something similar to the angel system. also that artifact of the supreme sorcerer who monitors magical activities on earth and to which I think the ministry has something similar, along with some magical circuit of destiny made with a piseudo spiritual material to serve as an organ and at the same time not interfere with the functioning of other bodies
The story has been interesting so far but my main drive was the "OP Harry" in the book's description and, while he is indeed quite OP compared to og Harry (It doesn't really take much tbh) I truly can not see how will he ever be OP in the DxD universe, I mean there are World destroying threats left and right and this guy doesn't even have a system, nor any added special bloodline of sorts, not even a longinus sacred gear (although he might develop a way to steal one or multiple later on, but for now it doesn't look like it will be the case) so I'm quite worried that he will fall off hard or that he won't really be that relevant to the greater plot once the focus shifts from the magic schools to the World at large.