Well, how many can you draw in a week? If you can do two or more without it being taxing on your freetime, I'd say go for it. One to three panels is a bit short for once a week, so I'd say two a week would be better.
But only do that if you think you can keep with it, imo. If you think it might be unreasonable for one reason or another, give once a week a try for a while and ask yourself again later.
It looks a lot better if you start low and increase how many you do weekly than if you decrease. I'm doing a bit of catch-up right now since I'm determined to do two updates a week, but I'm incredibly busy and each page takes several hours. Anytime life throws me a curve ball, things get messy. I'm doing one update a week until November - no one's complained to me, but I just get the impression I'm letting people down.
If you don't already have one, build a buffer before switching to two a week (if you do). So if your plans change, you'll already have the next update prepared and won't have to worry about finishing it up just a few hours before you plan to update.