Some hand dyed is more even than others. My usual way to do it is to dye up from the washed fleece, then send to the mill for carding. their picker/blenders do such a great job, you'd never know the dye job wasn't so great.
OTOH, when I do the carding myself, there are always variations. I don't mind them, but if I were to try and avoid them, I'd alternate rows as above. Or better yet, work a simple 2 color pattern, even tho you are using only one pattern. (would that be too hard?)