One more feat for DnD Next…
Dice Explosion
Feat
You have trained to make your devastating hits even more crushing
Benefit: When you roll maximum damage on a weapon damage roll, you reroll the dice and add the new total to the maximum damage roll.
Thoughts?
Throat Punch Games 
Just no
Do they continue to explode, or just once?
So of the two people who commented, there is the entire spectrum of ideas here. laverafish loves exploding dice and I’ve seen her gravitate to games that have that. I don’t know about shroudeye. Do you not like those games?
As for continuing to explode, sure. If you get lucky enough then go for it. Honestly, that would be something you would need to playtest.