I see things differently.
If all you want to do is run "lots of things", "many different types of functions" there is nothing stopping you from putting many functions in one script. You can even do error checks and stop functions from running without throwing the whole script. --see my Return() script below.
The purpose of includes is to reduce the amount of times you have to code the exact same script.
If I have 100 different scripts, all of which define a=1; b=2; c=3; ... so on to zz=702, you wouldn't want to type this all out 100 times. Without includes, most likely you would type it once and copy and paste into your other scripts. But what if down the line you find a bug? You'd have to go into 100 scripts and manually fix the code. A tedious job. But what if you end up finding a faster way to perform the same task of defining all these variables? You'd have to refactor your code 100 times across all the scripts. What if you decide you actually want a=2; b=3... ect. You'd have to change your code 100 times. Changing 100 scripts is an error prone task, what if you miss a script, make a wrong change, ect?
The purpose of includes is not to create a slave/master relationship where you can kill the slave and save the master. We have functions for that. The purpose of includes is to save time coding.
(Note: Another purpose of includes is to help keep scripting languages separate making it easy to debug and keep code clean. Includes are especially helpful in web applications with HTML/CSS/JavaScript, but this doesn't really apply to JSL.)
Passing a check variable has a few problems not many but a few. What if another script uses the same check variable? What if I decide to change the check variable? What if I mistyped the check variable? In each case, I'd then have to go and find every script I included the throwTest.include and edit the check variable to be correct, which defeats the purpose of using the include in the first place.