Hi Narwan
The 70mm is a good and a bad example at battalion level it was heavier than the equivelent in other armies, a mortar. At divisional level it was lighter than the usual 105mm (though the Japanese did have a 105 and 150mm howitzers in common usage). The British had the 88mm (25pounder) as the standard infantry divisions divisional gun. But nobody would call the English light infantry.
So... the Japanese infantry divisions had just as much artillery as any other countries sometimes more, ie the standard 3 battalions per division but also their regimental guns, missing in most other countries TOE.
They had engineers and Recon, antitank and antiaircraft assets and sometimes tanks.
So So they dont have "fewer heavy equipment" other than that their artillery was lighter than the equivelent calibre in other countries. By your definition Mountain troops must also light infantry?
check the Japanese OOBs at this site
http://www.fireandfury.com/extra/ordersofbattle.shtml
http://www.fireandfury.com/pacificinfo/japanese.pdf
http://www.fireandfury.com/pacificin...anjapanese.pdf
http://www.fireandfury.com/pacificin..._jpn109div.pdf
http://www.fireandfury.com/pacificin...aneseburma.pdf
Best Regards Chuck.