using only GH components (no scripting) I would approach it like this:
Random tiling_1.gh (21.3 KB)
the gene pool allows you to weight the different cell groups
consider that the A part of definition is sort of bad 
somehow when doubles are transformed into integers and some rounding happens, we need to find a culprit to make the final total number of cells to be = to the total number we have generated
in this case the culprit is item at index 0, that gets recalculated as (total number of cells) - (sum of all the other used cells)… there for sure will be smarter methods, this was the fastest shortcut I could think about
this slider allows you to shuffle the cells differently:
B is probably the only thing that matters: it outputs a tree with 10 branches, each branch containing the cells that belong to each different group
