Storm is wicked fun, but I think you'll find it difficult to make it competitive without being poisony. I think it would be best suited for P9 cubes.
I've also been doing an artifacts theme in red like Onder's.
I haven't played around with tribal too much but squadron picks of cards has been a success here. Balancing it hasn't been as difficult as one might think. Sometimes it makes life easier because it lets certain cards BECOME more balanced since it's a double (like Goblin Welder: having two separate ones can be poisony and a bit clunky, but a single double-pick has been perfect). I've made several aggro 1-drops into double-picks so that aggro can get what it needs without cluttering up the cube with cards that most drafters have no interest in.
Going tribal beyond humans and zombies might be tricky without knocking the power level of your cube down a couple ticks, even with utilizing double-picks.
Edit: on second thought, maybe you could get storm to work by focusing on Empty the Warrens specifically and overlapping as much as possible with "spells matters" archetypes. Free/cantrippy spells, etc. probably include 2 or three separate copies of Empty, or a single double-pick. Much easier than the other storm spells because you don't need to go as high to make it worth it, synergies with Purphoros, Goblin Bombardment, team prowess, etc. Now I kinda want to experiment with that.