Both cable and lace are not as complicated as they look.
The difficult part of both is just keeping track of stitches and rows.
I personally like lace better, only because I'm not too fond of that extra little needle (cable needle) you need to deal with, and the fear of dropping the stitch while transferring the stitches onto and off the cable needle. Also because right when I come to the cabling point, and because you're pulling the stitches towards or away, you kind of have to squeeze your needle and struggle to get through the loop. There are ways to do cable without cable needles (which I have yet to explore), and the good thing about cabling is that most of the time, after a cabling row comes a couple rows of mindless straight knitting.
The struggling to knit the further stitches only gets obvious when there are more than 5 stitches you're crossing over. (Also keep in mind that the 'cross-over' of these cables make the fabric thicker in that area and makes more warm fabric!)
But anyways, unless you go fancy and try to make different interval cables running alongside each other, cable is easy, because other than the cable needle, all you need is the ability to do a knit stitch and purl stitch. Sometimes you don't even need to know purl, but most cables have a purl stitch or two on their side in order to make the cable more obvious. Depending on the kind of cable, it gets 'lost' in stockinette background. However, by having those extra purl stitches (a ditch, basically) on either side, the cables pop out.
Anyways to conclude...do not fear cable. It is NOT hard. Just make sure that you place a row marker or something to indicate where you started that cable pattern repeat. And make sure, to REMEMBER IF YOU PUT THAT MARKER AT 'BEGINNING OF THE REPEAT' OR 'END OF THE REPEAT'. And also, IF YOU'RE PLACING A STITCH MARKER, PLACE IT SOMEWHERE IN THE STOCKINETTE ZONE.
It sounds simple, but believe me. I've screwed up many times, especially when I put the project aside and come back to it in few weeks. If you don't remember where exactly you placed that marker, its just as useless as not having any markers. Write it down somewhere if you're bad as I am. Counting rows on a stockinette is easy, but its a bit harder to distinguish where exactly the actual cabling occurs, once it is done.
Lace, on the other hand requires more techniques. Yo, k2tog, ssk, sk2p are the most common, and sometimes you get some weird stuff like k2tbl (knit two through back loop) .
So technically speaking, though most of those stitches are similar, lace is more advanced. However, if you ask me if it is "easy" or not than cable, I almost feel like once you know how to do those stitches, lace may be easier.
Easier in a way that---you may want some stitch markers for wider lace project, but you don't really need anything. K2togs and sk2ps and stuff, you can do without any additional tools like the cable needles. That's partly why I prefer lace project for commuting knit project. Pulling out that small cable needle, transferring stitches while you're been rocked by the train is a bit more scary for me.
Once you get used to lace, it is FUN. Yes you'll most probably need to print out and carry around your pattern, crossing them out as you go, and its kinda messy to tink because there are so many complex stitches. But the is something called the lifeline (yet another thing I need to explore), but I just make sure I get the correct number of stitches each time. Usually the WS is basically purling, you only really need to check stitches every other row. By the way you probably don't want to work on it when you're a bit sleepy or braindead. (and that's when mindless garter/stockinette project comes handy!). But for other times, esp for morning commute, its like a nice little brain-stimulating puzzle.
Anyways, both cable and lace is 'easy' in their own way, and level of complexity also depends on what cable/lace pattern you're using. I hope this article helped some beginner+ knitters to take one step forward. Don't be scared! =P