I'm strongly in favor of giving the parliament the ability to propose laws (directives). Currently only the comission can do that.
The way it seems to work in practice (here at least) is most partisan/normative legislation goes through the lower house upwards
And bipartisan (or broadly unpopular or highly technical) legislation goes from the upper house down
It’s more complicated than that, but a one way flow committee sounds extremely restrictive for meaningful reform
A small number of pathways is a good thing, one lone process is probably not (you risk over fitting on both sides)
Edit: Australian legislation has a lot of flaws, but this multimodal setup from my experience is not one of them
The EU system is also not without its flaws but it's not the worst. Enacting broad, sweeping legislation is cumbersome and difficult which is a feature, not a bug. If we had a more streamlined system we'd probably already have chat control by now.
Also EU can't actually make any laws it makes directives that are then up to each member state to implement on their own. It also has no police/military/force to actually enforce that the member states implement the directives. Basically everything is very much about cooperation or finding a compromise everyone can agree on as there is no way to force anyone to do anything really (outside of cutting away EU funding but then the member state can also stop paying their dues which does not work for most of the big states as they pay more then they get back)
The thing where EU has power and actual means to enforce things is the reason it was originally created for. Trade.
But yes, the whole thing is of course based on cooperation between states. EU law applies in EU member states (whether directly or indirectly) because those member states say so.