It's not clear what the advantages of pure imperialism would have been at the time vs taking advantage of all of those exact pros you mentioned without outright

It's not clear what the advantages of pure imperialism would have been at the time vs taking advantage of all of those exact pros you mentioned without outright taking over of nations. Global hegemony shifted from pure colonialism to neocolonialism over the few decades and it's still to be determined what the next wave will be.