'It is one of the most remarkable features of the age of discovery that the lead in exploration was taken by the small and economically backward kingdom of Portugal. With a population of about one million in the fifteenth century, a dearth of fertile agriculture land, no tradition in long sea voyages and few good harbours, Portugal seemed to have little to recommend it when compared with, for example, the rich and economically sophisticated Italian states. Virtually its only contributions to European trade was fish, salt, cork and olive oil' Years of Renewal European History 1470-1600
If anything Portugal should be nerfed by alot, if you want it to be historical. It was only ever luck that allowed it to expand to a colonial empire. It should certainly not have its power increased, in any way, as its current status is very ahistorical.