i do commercial illustration using photoshop, illustrator and work with allot of 3d and photography integration for advertising. im also in school studying entertainment design.
i think the pro is fairly capable for your workflow- making graphics like those is not very resource intensive, but i wouldn't want to not have a desktop available for file management, and color space conversion. you dont need a fast computer, just something that can run desktop software. the ipad pro does not have color calibration, which matters for some illustration and design work.
i use my pro for beginning projects, sketching, or basic vector art. after that i push to my desktop and work on a 5k 2016 imac with 4ghz processor, 32gb ram, 1TB HD, and this is hooked up to a cintiq 27 that is color calibrated once a month. No color calibration is a sure sign of amateur work. I get paid by the hour and desktop software is much faster with a cintiq. Keyboard hotkeys and buttons on the pen make a huge difference in commercial art. But it takes years of training to get to this level, for most people the ipad is ideal. you have to decide where you stand with your skill level, and where you want to go in design.
i think the ipad pro is an excellent companion device. its not super powerful like a desktop, but its pretty quick for a mobile solution. i love it for what it is, a mobile content creation tablet. Its very far from a mobile workstation though, like a macbook pro or cintiq companion. these machines are much faster. i find ipad pro to be a little slow for editing RAW photos or doing video edits, it gets annoying, and can only do basic editing. I do use my Pro while traveling for posting from my DSLR to Instagram, at home for fine art photography id just rather use my desktop. its really allot faster. Plus, again, color calibration matters allot if you print your photos or even if you want accurate color for web.
my hobby is drawing and painting, and for that the ipad works really well. i just dont use it for anything i want to print large (bigger than poster size), its limited by a mobile cpu and small amount of ram. But for anything that stays on the web its ideal. im using the 12.9 pro.
hope this helps.