I would like a tatoo sleeve but does just one look silly? is it usual to have both arms done? I have two tatoos on one arm and three on the other.
I am a tatoo artist and if one suits you then one it is, you have plenty of time to decide for yourself just make sure you get a component artist to do what you want and that will be there for the time it takes to get your tatoos.
I think two tatoos looks better than one. Just my opinion.