Hey Gald,
After reading what Handoko wrote, and from a recent experience with code from a person that didn't went the OOP route and instead opted for the Procedural way and having units to group those procedure/function by his arbitrary rules, I now have another question:
How well versed are you on OOP?
I ask this because it kinda sounds like your decision to put Event handlers in other units is what that other fellah did with the procedural approach.
I need to stress this out: No shame what so ever.
But you have to pick a lane and stick to it.
And by that I mean, you either go OOP and every object has his own unit, of sorts.
Or you decide to go all in with the procedural approach and you spread your code in a different way.
If you embrace the OOP methodology, I think your code will be a lot kinder to other programmers.
If, on the other side, you are going for the procedural approach, then your code will be considered spaghetti by the majority of the programmers that only have patience for OOP.
But at least it's your spaghetti and you'll know how to navigate it. But, alas, you'll be a solo programmer on this one for a long time
So yeah, pick your lane, stick to it and PLEASE pay attention to the VERY GOOD advice that Handoko gave you, it's rather good and very valuable!!
Cheers,
Gus