karel,
With these weights, you could spend years trying to find exact matches for all canes in any one weight. There were so many weights of this design produced each using a small selection of a vast array of available cane constructs. They were not put together by choosing specific canes - just selections from those at hand at the time. My planned table of Strathearn canes will, I am sure, fall very short of the numbers that are possible.
You are right that the design is not quite the same as a standard closepack, which has canes set without any apparent order. And, for my own purposes, I do refer to ones that have definte rows as "close concentrics" - but only if (as you have spotted is not quite the case with yours) the rows are actually independent and do not merge at some point or have extra "stray" canes set amongst them. For general purposes, Strathearns of this pattern are more easily described just as "closepacks".
The number of canes per weight is not something that I have yet found to be meaningful. It mostly depends on the size of the canes used - if they are all of the same general size, then more can be used to fill the available space than if a sizeable percentage were larger. Also, bear in mind that the canes would have been set out in a circular "former" and it would be natural to fill up the outer edge first then the next "outer", and so on. Each "row" could have "indents" because of the different cane sizes and if those "indents" were not filled with an appropriate size cane in the next "row", the pattern would quickly become non-concentric. [However, I gave not actually seen the canes for a closepack weight being assembled - there could be other ways to do it than the general idea I have suggested.]