I agree fully, Portugal is taking the Santa Maria wonder in almost every game I play. The AI has a huge aversion to trading for Patronage too. They'll usually only offer 10 gold for it. Starting with doctrine lets them fire up the theocracy (arguably more useful to Portugal than vassalage) and fanaticism combo from the start. Historically speaking that civic combo is more representative of Renaissance Portugal, but on normal speed there just isn't enough time to LARP as medieval Portugal, you have to get started on your UHV immediately.