Dark retribution will become a super shard bomb, capable of doing what all of the shard bombs are capable of now which is to say effective damage vs everything at the decreased rate + stun + shock + slime v. high + fiend v. high, all at once but none mentioned in the tooltip. It would be called fairly neutral yet strong against oddly specific enemies retribution and its description would be "Seerus loves surprises and hates Mondays." Having this amazing shard bomb would make up for how collectively poor shard bombs are currently, to the point where players would actually consider using it. You could even keep the invincitink bug that 99% of players don't notice or care about because they've never actually seen a shard bomb used before.
The current shard bombs would all gain the floating orbs of godly damage per second without knockback effect, with their current effects in play which is to say that salt bomb and sun shards would have less damage and shock/stun/monster buffs. The new bombs would be amazing and bombers would love them, unless they had some ridiculous qualm that doesn't actually play out the way they think it does which is to say roughly 1/3s of bombers will hate them-- a definite improvement from the current 1% and I am not talking about wealthy Americans here.
Why would you do this? Because dark retribution is an effective bomb and the shard bombs aren't, so it would make sense to make the shard bombs, a harder to learn + typically weaker alternative stronger and hidden away behind operation crimson hammer with dark retribution, a strong, easy to use, reliable DPS monster the main damage dealer for bombers.
Now we could have dps bombs for each damage type. I think that shock on a DR style bomb will be pretty OP. There will be those people that rely on their DR though and they will probably be not too happy. I also think that it should have a similar learning curve to a hammer with a similar amount of reward to using it.