For these I think I like Miyuki round 11/0 or 13/0 the best. They are not quite charlottes (like standard Czech seeds) but are shaped more like a rounded tube bead, and are fairly uniform. I still have to eyeball them and pick out consistent sizes...but they are far easier.

For flat stitch (aka applique) I prefer Czech beads, because I like to have all the different thicknesses to fill in with.