If you're a content creator(and they bring food to the table, as well as pay for the roof over your head), I'd opt for the i7 as the saying goes, time is money. The less time you spend editing/rendering your work, the more easy it is to generate that income. As for your potential processor/platform upgrade, mind sharing the games and app's you'd like to work with as well as the streaming platforms?
I'd opt out of the i9 since it's from an older generation. Yu posted this thread in the motherboard's section yet the question is geared towards a CPU choice...have you looked into a motherboard yet?