The story is set in Poland during medieval times, with the MC reborn from a modern gamer playing the game, to a novel coming from an illustrious background. He's respected but he's middle-lower echelon in terms of nobility.
He knows a bit about this part of history, yet what truly gives him the foundation to stand out and develop is that he knows one simple fact about their current king, which is that he will abandon his kingdom and flee in 4-5 months time.
This isn't something that by itself will make him rich and powerful, but it gives him the opportunity to take advantage of that fact. The way he's growing his influence, wealth and power is by making innovations and improvements to already existing things.
For example, his beer business is doing really well, and he has expanded to 3 territories 112 chapters into the story, (all 3 of which are his, haha). His beer is considered to be on a different level, and knowing this he made it famous by using a couple of opportunities to make governors and nobles try it during noble social events in order to spread it.
There's no ridiculous cheats, he doesn't get thousands of gold of income after a couple of chapters, hell even after 112 chapters that's still not the case.
While from what I've said so far you might think that the MC's just good for making money, that's not the case. Funding an army is not so easily done, especially when your territory doesn't make enough money a month to open up a solid business.
There are also the issues of manpower, which can't be solved in a short period of time by regular means, which means he needs territory if he wants more population fast.
I can go on and on, but basically, him focusing on economic development so far is mostly because he needs it as a foundation to grow further.
The main point that has attracted me to this story, is that the MC isn't a knight in shining armor that will risk his life for nothing. He's neutral, which i can deal with.
The main issue I have with it however, is that while he kills most of his enemies, I don't find him ruthless enough. *Spoiler below this*
Most recently, he defeated the man that wanted to take his wife as his own in a war in which he killed almost all of the enemies soldiers, and after the man stands on trial and is exiled, he doesn't off him after he's exiled. Yes he's already gotten all of his territory and money, but offing him is no problem and I don't see a good reason for him not to do it. Some smart nobles would know it was him that made his enemy mysteriously disappear, but so what? It's not uncommon and there won't be proof.
So far the author has shown that he doesn't use tropes, but if the exiled guy with nothing to his name makes problems for the MC in the future, that's grounds for dropping the book.
Overall it's a great novel, among the best of its rare kind. Novels similar to this are Black Iron's Glory, The World Online, etc.