Hi Nicola
Roon provides little if any customization but it does something’s very right, as with any software there’s a learning curve. I did the one year $120 “trial” , 2 weeks doesn’t scratch the surface. Beware it is addictive!
If you dig in a bit the Composer view looks ok but a bit bewildering at first. Roon tends to demand a lot of typing even just 3-4 letters to get around where others don’t primarily due to the customization you seek
I too got frustrated at first but you do settle in to it. The bigger issues of classical music are discussed in depth in many post, maybe search the forum.
You will (have to ? ) learn new ways to navigate but if you like the info presented and how it’s presented then it’s worth it. The big plus is that you don’t have to groom metadata (much) and that saves hours of keyboard effort, if you have already done the work it is a frustration not to be able to use it
Bit wordy but try getting around using
Album focus
Composition view filters
Composer view
I switched from Composer first to Artist first …
Good luck