One aspect of Guilded Iconography is the Iconoclasm decisions. Instead of tax penalty, you get a tax bonus, CT growth substituted by CT decay, big missionary bonus as well, some cash and minus 3 stability. I always enact it as soon as I get to Academies of Arts. Usually building them in high income, non-capital grain provinces (Kiev, Moscow post St-Petersburg move, Alexandria, Rome, Thrace if I am not Byz). Someone said earlier in the thread that tax income is worthless and imho that is crazy. I had game where most of my income up until mid 18th century was taxes and it was not because my production or trade tech sucked. Especially in my last Byzantium game, a series of national decisions, Iconoclasm, Church taxes (easily available for Orthodox), Land Reform and Land Enclosures in high base tax provs thanks to the magistrate producing machine a successfull Byz can become paired with high admin monarch or two, my tax income is unbelievably high, so is the base conversion chance which helps to create a mono-religious state even though I constantly keep expanding into Persia, India and Central Asia. Iconoclasm is not always worth it and situational, since you do need to handle -5 CT, but it can be an awesome decision to take.
Back to original question, most games I take CAD for GI, then switch. As Trader to NTP, if not trading much then usually Patron of the Arts (especially if I ever plan to westernize). If I plan to expand while already in posession of many cores (any major and resurgent Byz) I might take Battlefield Comissions. If you can field big size armies, the MT flow can get pretty slow and playing a big nation I find the ability to field 2-3 shock 4-6 generals tends to help me more than 1 morale. If I play as Portugal/Castille I might swap out to QftNW as soon as I get required trade tech.
PS Also for some nations Iconoclasm can be cool for RP reasons.