I just find them more appealing than the Hexi-Cardigan that everyone seems to do. I have seen a lot of Hexi cardis in odd colours or that look very bulky and it puts me off as I don't feel it fits with my style. I have seen some lovely ones as well, but it makes me worry that I would invest lots of time and it would not come out right. I also have no faith in my ability to make 2 identical hexigans
I think Sirdar's Hoodstock pattern is easier and less bulky than the hexi-cardigan, but it does need to be sewn together. It's a rectangle for the back, smaller rectangles for the left/right fronts/sleeves and a square for the hood.
It's easy to adapt, I made it longer than the pattern and added wooden toggles, fastened with chain loops. I did make the hood, but made it larger.
The hood is made separately and sewn on, so you could make it without the hood, if you didn't want it. The pattern is crochet shells, rather than granny stripes, but still easy and has a similar look to granny stripes.
Stylecraft have some crochet cardigan/jumper patterns, which are also fairly easy to follow.