I like to try different colorants in glazes. I usually start with a good Clear I trust. If it then acts up, I can be confident the additions caused the problem and adjust accordingly.
My favorite is
cone 8-10 redux or ox.
Viscous, predictable glaze. Good for classrooms and/or a second layer of glaze since it doesnt run much. Turn matt glazes to gloss with a top coat of this glaze. (one quick dip color glaze, dry, then 1 dip Clear Gloss.)
Ball Clay (Kentucky Ball works well) 10
Custer Feldspar 40
This is the base the makes the Blindingly Bright Green found at http://www.websitetoolbox.com/tool/post/clayarts/vpost?id=1263588
This is a tried and true glaze. I have personally used it in large gas kiln, little gas kiln and electric kiln with a cone sitter.