So this is a suggestion to make Deadly Shard Bomb worth it, if only in the most extreme of circumstances.
Basically, you raise the damage. But there's a twist! You apply the following bonus to it:
Damage penalty Very High
The damage would be raised so that, with no damage bonus, the damage would be equal to what is is today. This allows you to stack +10 damage onto the bomb, but the first +4 would be at reduced returns (11% for the whole +4 compared to 16% usually), but the next +6 would be great in comparison. The end result is that the deadly shard bomb would be as strong as deadly splinter vs beasts, deadly crystal vs undead and deadly dark matter vs gremlins when they're at medium damage bonus, but you had to pump +10 damage bonus into the bomb to get it that far.
Basically it would make Deadly Shard Bomb worth it for diehard shardbombers, as opposed to how it is today when it's not worth it for anyone at all.
I've wanted to stack bonuses to an absurd height for so long, and deadly shard bombs sounds like a perfect candidate.