My first bike tours were accomplished without the benefit of front panniers. In fact, my first prototype Convertible did not include front panniers. There – I have demonstrated that it is possible to tour without them. Then I made myself a pair, and what a difference! Especially when pulling up a hill, the front pannier gave the front wheel some inertia, so I could pull on the handlebar without weaving all over the road. There is a big difference in stability, compared to weight on a handlebar bag! Please remember that your rack must be for an over-the-wheel pannier, not Low Riders.
I recommend packing your “high density” items in the front panniers, things like tools, anything metal, extra water, and perhaps rain gear. The Convertible Elite front pannier gives you 4 lower compartments and 2 (smaller) upper compartments. With a little practice, it is easy to distinguish them, so you can pack consistently and always know where to find a particular item (left-right, front-back, top-bottom). Even though there is lower volume in the front, your load will be well-balanced with the more massive items in the front.
I’ve never considered riding without the rear pannier, so I don’t consider the question “either or”. The rear pannier carries the bulky items that wouldn’t fit up front. Then it carries more – the things you hadn’t planned on. Dinner. Something too cool to leave it behind. Looking at fully packed touring bikes, 1) there’s too much stuff, and 2) it gets packed in back. So start with the heavy stuff up front – the back will take care of itself!