When I was thinking about purchasing the Khaki Field Mechanical, two things worried me: 1) the lug-to-lug length and 2) the lack of AR. But I pulled the trigger anyway. I've worn the watch for a month, and these things don't bother me anymore.
The lugs look perfect to me, especially on a NATO. Because of the very large crown, the watch would look strange with shorter lugs. The extended lugs have the effect of balancing out the overall design. Personally, I wouldn't change it.
As for the lack of AR, again, I wonder why I worried. Is the watch very reflective? Yes. Has it ever stopped me from instantly telling the time? No. Would I prefer some AR coating? No. I enjoy the pure sapphire crystal, which is exceptionally clear from every angle, thanks to the double dome.