Consider
Blossoming Sands/
Graypelt Refuge/Kabira Crossraods,
Radiant Fountain/
Glimmerpost and in particular
Interplanar Beacon. Obviously don't use all of these at once, especially since the first three can kill tempo and the last three are more colourless lands, but they are Heliod-triggers that can be pulled out by
Expedition Map and
Sylvan Scrying. They also make it easier to stay alive long enough to pull out Urzatron and play the heavyweights. Maybe the respective penalties are a bit too steep for any of these to be worth putting in, but they should at least be worth looking at.