For me, planning what gets done each day helps me get more pages done.
I complete 3 pages a week- so what I do is give myself a day to plan my thumbnails, composition and backgrounds, 2 days for sketching, 2 days for lineart, one for colouring and one for shading. By breaking it down like this, it means I have a bit of work to do everyday that isn't too much to keep up with.
I find that doing all the sketching/lineart or whatever process for a couple pages in one go really speeds things up since you don't have to change your process for each page, and you have that momentum.
This can also help you find out what takes you the most amount of time to do and plan accordingly. For example, if you know sketches are quick but lineart is slow, spend a day on sketches and a couple days on lineart.
Hope this helps!