I just finished this scarf: pieKnits: Ropes and Ladders Cabled Scarf Pattern
for my grandmother. I used 7mm needles (US size 10.5 is 6mm) and I think it came out nice. I didn't do 21 pattern repeats, though, because that would go to her knees. I only did 14.
The cabling is easy, and I learned ssk with this pattern. One tip, though! Use a blockable fiber because the sides tend to curl up.
Good luck finding a pattern you like!