Often when used as a transport it was with seats (like an airliner). It had a very small interior, and I VERY much doubt it could carry 16 fully geared up paratroopers. Further, the pre-eminent Luftwaffe paratrooper delivery aircraft was the Ju-52. The Ju-52 was also used as a bomber, but it was not considered a bomber.
In the same line of thought, the He-111 may have been used for troop dropping a few times, but it was NOT a troop transport. It was a bomber.
Let bombers be bombers, and let transports be transports.
You want an axis transport, that's where you should ask for the Ju-52. We need the He111 but as an early war bomber! Not as a transport! (this game desperately needs more early war light bombers -- you really can't run any scenario before 1943 these days because of lack of early bombers!)