Having worked up my leather working skill to the point where I can now work ulbernaut furs, I think it is time to make a comment. It appears to me that the leather work table is too small. Only 7 ulbernaut hides can fit on a table at one time and apparently 4 hides that are larger. This combined with the fact that there are only two tables available in the game makes for extremely inefficient work flow. More and larger tables would be greatly beneficial, alternatively you could allow furniture tables to be utilized for this purpose as well as for casting rings. I understand that would be more problematic and you would need to alter the rules to allow these different containers to be used.
The fact that ulber hides take up almost double the space as tefusang hide seems to mean that they should produce more leather, if this will not be the case perhaps explanatory material can be added to the leather working books in the library. I have not actually looked lately to see if such material has been added lately, I just assume it has not. Be that as it may it would seem the only reasons for using such larger hides is greater practice and greater experience in the hunt, both of which are Out Of Character considerations.
Anyways just a few thoughts that have come to mind.
