In the UK and other member states of the EU, "Brussels" are accused of producing complex, too much or simply bad laws and that is used as a premise for arguing against a deeper union or even return of (reclaim of) EU legislative competences or existing EU laws "back to" the national level!
Yet, over-regulation and over-legislation are not an endemic element of a deeper EU. There can be a deeper EU with fewer and better regulations and laws, but that means at fewer and better regulations and laws both the EU and the national (and state eg laender) level! And to a large extent of course the full replacement of national and sub-federal laws in some members states with federal structure (eg Germany) with EU laws. And a model of full shared EU sovereignty.
In other words over-regulation & over-legislation is a perennial (national) problem in most Member States that, "simply", has been "transposed" to the EU level over the last decades via the transfer of policy and law making mentalities of the member states to the EU level. And most politicians who accuse "Brussels" of over-regulation & over-legislation choose to ignore that same problem in their own countries!
Hence, there can be a better regulated and legislated deeper EU but some politicians in most member states must be willing to cut the BS.