Patron of Arts is obligatory for Europeans

[ForzaA]

When you need it the most is the first century or two depending who you're playing.

Incidentally, this is also when you need other ideas most

Magistrates can't replace it. You needt hem for provincial decisions and you need really many. Land reforms, enclosures, formalizing weights and measures, road networks, post offices, monuments, there's plenty to do with magistrates than spending them to boost culture.

Depends entirely on who you're playing. I had magistrates coming out my nose as Byzantium f.ex.

 

[ForzaA]

The good part is that patron can double for a bunch of ideas. National Bank, National Trade Policy, Church Attendance, many more. There are a few countries who don't need, HRE doesn't, he has his own bonus, neither do Muslims or Byzzies. But everyone else, all the medium powers can gain from flexibility of Patron which other ideas don't grant.

Flexibility, sure. But I'd say this makes it a valid choice, rather than a "must have".

Sure, it can "double" as national bank, but it will still cost you that advisor slot that you might have filled up in some other way.

Granted, at the moment I wish I had it playing as TEU (pickings from the pool have been poor at best)
BUT, it's not like I don't need my Deus Vult (need to find a power base somewhere; Russia is a good choice) and National Conscripts (suffice to say that starting of with a few HRE provinces and no way to join the HRE does get the attention of the Emperor)