A few disclaimers... First: this was done by request and with permission
Second: I am blessed to ski in the land of wonderful bumps at Mary Jane, Copper and A-basin. We usually have great lines with nice snow. I'll usually try to ski similar lines to these when the snow is firm, mostly for the challenge, but I'll also change it up and try to turn wherever I can find soft snow.
Third disclaimer: I'm just a hack who likes to ski bumps, not an instructor, coach or competitor (unless you count a couple amateur college bump comps over 20 years ago).
That said, here are a few roughly drawn lines, the first being the zipper line. I'm always looking for a good zipper line, and when available it's my duty to ski it! When not available, I'll usually try to make one out of what is available. For me, a good zipper line is usually the easiest (least effort) and fastest way down the hill. If the snow is firm, I'll probably move over from the "big boy" zipper line to another zipperline with ruts that are not as deep.
Second is a more rounded line. This is a slower, easy going line I'll sometimes take. I've been skiing this a lot recently on my fat (110mm) rockered skis at the end of a powder day. Unless there is a lot of new snow, my fat skis are just too much work and too slow edge to edge to ski the zipperline for very long. This is a great line for folks learning bumps, as it's easy to control your speed, and even stop on the back side of each bump if you like.
I also enjoy a fast GS line when the snow and bumps allow it. This is often possible at the top or on the side of a bump runs where the bumps are smaller and more spread out. Fortunately, we seldom get ice patches between sparse bumps, otherwise this line isn't any fun.
That's just the way I think about it. @Bob Barnes has thought this a whole lot more, and put together a great video showing a whole bunch of different lines and folks skiing them nicely: