Both the Splinter Bomb and Dark Matter Bomb have alternate status-inducing lines, but the Crystal Bomb is sorely lacking; I propose the Ice Shards line to fill this gap.
Justifications:
-The Rock Salt line counters a piercing-type family (slimes) and the Sun Shards line counters a shadow-type family (fiends), so it would make sense for the alternate Crystal Bomb line to cover an elemental-type family which is weak to elemental (i.e. constructs).
-The Rock Salt line and Sun Shards line both cause crowd control statuses (shock and stun, respectively), so it would be reasonable for the alternate Crystal Bomb line to cause a crowd control status as well. Freeze fits this bill nicely, as Fire, Curse, and Poison are less crowd-control oriented.
-Damage scaling would follow the same patterns that the Sun Shards and Rock Salt lines do, when compared to their raw-damage counterparts.
★★★☆☆ Ice Shards
Damage Bonus vs. Construct: Very High
A shard bomb surrounded by fragments of Moonstone and Hailstone. It's cold as ice, and willing to sacrifice your foes.
10 Blue Shard
3 Ecto Drop
2 Owlite Feather
1 Hailstone
3 Advanced Orb of Alchemy
★★★★☆ Hail Shards
Fair chance of causing Moderate Freeze
Damage Bonus vs. Construct: Very High
A solid chunk of Hailstone with an explosive surprise inside. Retrodes hate surprises.
15 Blue Shard
4 Ecto Drop
3 Owlite Feather
2 Hailstone
1 Perfect Snowball
3 Elite Orb of Alchemy
★★★★★ Hailstone Barrage
Fair chance of causing Moderate Freeze
Damage Bonus vs. Construct: Very High
A large chunk of Hailstone primed with explosives. When you absolutely, positively got to freeze every constuct in the room, accept no substitutes.
20 Blue Shard
5 Ecto Drop
4 Owlite Feather
3 Hailstone
2 Perfect Snowball
1 Everfrost
3 Eternal Orb of Alchemy
Your suggestion might be recognized by the users but definitely not by the developers(applies to all suggestions).
The idea seems balanced to me so... yea.