do you have any specifics you would like to see expanded?
Now there's a dangerous question to ask

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Note, the syntax I refer to below is either made up or a rough approximation on what's in HoI4 now - it's not intended to be precise.
Being able to set a mod-created variable (for example "set_country_variable = {variable_name = max_army_size variable_value = 10}") that can then be adjusted through scripting events (If MIC > 50, ten variable is increased by a set number) and queried in strategy, event and modifier triggers would be mega handy. Having some mathematical operators to work with the variables would also be necessary (just +, -, *, /, =, <, > would probably do the job).
If these variables could also be reference in localisation text, so that you could have a variable that measures how long a nation has been at total mobilisation, you could then have an event that said "Your nation has been totally mobilised for [variablename.getvariable] months, but there is no longer any serious threat, national unity suffers" that would also be handy.
Finally, having some kind of "hidden event" that can fire to adjust the variables without players being notified would also be handy (using the previous example, a hidden event that fires regularly to count how long a nation has been at total mobilisation, incrementing the mod-created variable each time). I think this can technically be done by firing events for the AI that make changes to variables affecting a player, using random_country and is_ai = no, but I'm not sure how well this would work for mods designed for MP play.
I totally appreciate that the above is a rather big ask, and I don't expect it to ever happen (I expect it would take a lot of work), but if you were looking for specific ideas......

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