As someone who decorates a lot of cakes, I'll tell you that canned frosting is too soft for most decorating and needs to be stiffened by adding powdered sugar, but then it would be very sweet. What you could try is to refrigerate the frosting overnight and refrigerate frequently while decorating the cake.
Do you have a Gordon Food Service (GFS) store near you? They are a foodservice retailer that sells to the public too. I have found a whipped frosting mix there that all you have to do is whip it until stiff (don't need to add anything) and use. This mix takes color well, too.
I mix a container of coolwhip with thing of icing,it goes on so much easier,and taste yummy.I like the buttercream icing,and separate it into small bowls,to mix for coloring,goes alot further too.
Yes I am Betty Crocker.lol