Before jumping to , to many conclusians Battara , as you rightly note, you should persuade Simon to post photos of all the kukris of similar date in that museaum... Although those posted doe show trends in some ways, there many styles of blades even in the early days.... Some of the more exotic blade shapes probably show more regional areas on some occasions.
{Nepal bieing many kingdoms at that time. {over 500 I recall?} plus some Bengali stuff of course.}
But yes it all helps the learning... think I took about 200 photos there in 2005. {Simon thought it funny , I took so many at the time.}
Still he did pose in front of a couple of displays, while I was taking them, to add something to the pics...
Spiral