I'm thinking of moving some of the dice values around to make deterring success without strife, i.e. simple rolls, go quickly. Roll20 lets people play online, but it also makes a game like L5R hard when in many cases all you want is a success/failure.
So, the changes would be:
D6: Blank, Opportunity / Strife, Opportunity / Strife, Success / Strife, Success, Exploding Success
D12: 1-2 - Blank, 3 - 5: Opportunity / Strife, 6-8: Success / Strife, 9-11: Success / Opportunity, 12: Exploding Success / Opportunity
Mainly this has the benefit of making a simple roll: 5 or 6 on a D6 and 9 or higher on a D12. And exploding behavior that roll20 can handle (highest die value).