it depends - id say story quality is always priority. i will wait years for a good story, art be damned. although id question why it took so long if the art was bad. on the other hand, if im not really feeling a story but love the art, id appreciate infrequent updates because im really just looking at the pictures - but you dont really want that kind of reader.
if you want more subs fast, or your subs complain, drop your art quality, you can probably afford to. your first sacrifice will always be shading - try limited palette and shove a gradient on top, it looks great.
there are other ways to speed up, though! I personally go through the process of writing > drafting > drawing, and the problem with that is I get stuck with the long gap where im writing and drafting. what im trying to do, what you should do too, is build up buffer pages. while youre drawing, write too, and draft and whatever else. complete pages as they go, too - dont draw them all, then colour them all, then letter them all. your computer probably cant take all them files open at once anyway. if you have a steady stream of writing and drawing coming out, youll quickly overtake your deadlines and have weeks or months worth of backup - great for taking a break sometime.
start with figuring that out - take a hiatus for it if you must - and then if all else fails, sacrifice your art. (also, if you get tired out, sacrifice your art. seriously. low maintainence styles are step number one to avoiding burnout)