Basically everything you've stated is just called immigration policy.
I personally think we're too hard on skilled migrants and too lenient on relationship visas. But I'm sure I don't have a properly informed opinion, just a hunch based on my experiences.
"Funny", I'm a skilled immigrant with multiple friends whose marriage was torn apart by European immigration bureaucrats deciding theirs was fake, which if you see it play out in real life even once feels unnecessarily cruel beyond comparison, so I'm really wondering what kind of "experiences" you base your hunch on.
Have had friends struggle on skilled visas, whilst relationship visas with no schooling or skills all get approved with minimal fuss. My preference would be to make skilled migration easier.
Would have thought from a nation standpoint we'd want to attract talent.
Charges of sedition, vandalism or corruption are a favorite tactics against dissenters.