I've tried my hand at blending and I discovered real quick that blending tobacco is a very highly skilled artform. I did OK on simple stuff, like a little Virginia and Latakia, but for complex (and wonderful) blends like Mississippi River, Frog Morton, Captain Black, etc...you're better off leaving it to the professionals like Russ at Pipes and Cigars.
If you want something sweet, try Lord Methley from 4 Noggins.com. It is the sweetest blend I have ever smoked. My favorite sweet aromatics are Gawith-Hoggert's Bob's Chocolate Flake, Sam Gawith's Chocolate Flake, Kendall Cream Flake, and scented Broken Scotch Cake, Seattle Pipe Club's Seattle Evening (wonderfully sweet and smokey), Peterson's Killarney, and McClelland's Cream Vanilla Flake.