Sixteen is a good number for Goblins–they like to run in packs, and 16 is a good monster rating for them, too. A monster rating of 16 gets the goblin 2D6 + 8 combat adds–average combat roll around 15. Almost any first level T & T fighter can beat a single goblin in a fight, but 16 of them at a time might be a bit much. Time for strategy, tactics, and a quick retreat if you meet 16 Goblins at one time.
In 5th edition, Level 16 magic is for anti-magic spells and Exorcism.
16 is the Dexterity required to use heavy bows in combat effectively. It is also the Strength needed for a hand and a half sword–sometimes called a bastard sword. They called it that because they hated what it, not because they couldn’t find its father.
Sixteen is also for sweet 16–a very good age to start role-playing.
If you have some sweet 16s to add about Tunnels and Trolls, please put them in the comments below, and come back tomorrow to see if I have anything for 17 in Tunnels and Trolls.