Additional pics just aren't going to change the grade of this coin. One of the reasons the 1811 is so expensive is because so many of them (in my experienced) were struck on poor planchets to begin with.
Quote: It could be a dug coin, most of my older finds with a metal detector have had a similar look
just to add to your knowledge base. the classic large cents (1808-1814) were shipped in wood barrels from across the pond. during their transit humidity and salt water reacted with the copper. some years are worse than others. in this case the rarer 1811 is one were its very difficult to find one without some type of corrosion due to this.
i agree that dug coins can have this look but in this case its most likely the original planchet issues we are seeing. add to that prevalent striking issues across the series and low mintages results in less clean coins void of issues.
here is my 1808 (8 star) that looks like it could have been a dug coin. the coin graded VF25 details. this look is very typical of the series. you are going to pay a high premium for one that does not exhibit the planchet issues