Questions about Headquarters

[Mit Sigel]

So I am getting close to editing a copy of the Olympic.oob for Japan 45. And I have questions about headquarters.

I see no HQ's for battalion-size units. Is there a known reason for that? Like: The code doesn't allow it? Is it considered gamey? Does it create too many ant units? The stacks get too high and fall over?

I see no HQ's for corps artillery units or field artillery groups. 

I see no regimental combat/landing team organizations with attachments from supporting units. From reading the rules it seems like there would be some advantage to doing it that way. I guess my question here is: Would there be any harm in organizing teams?