Well, I am a Hybrid myself, but don't think immediately that I don't know what a pure bomber needs.

I have used bombs on many occasions and when I canceled a bomb charge, the bit of smoke puffs and got me thinking, "Didn't I see quite a few threads about mineral and block breaking options for bombers?" Then it hit me, the mini 'splosion of the canceled bomb charge can act similarly to a shock tick. The puff can damage enemies and hit blocks/boxes within a 1 or 1/2 square radius, not harming party members or the bomber him/herself. The damage on monsters in the range could be between 1-7, maybe 5 and possibly a 1-3 second stun.
This could help bombers with a few problems such as:

1) Having a room full boxes and/or minerals that are frustrating in the event of having to use 3 bomb charges (well excluding Dark Retribution line).
2) Needing to get away from a close rang enemy, stunning give you a speed advantage for a sec.
3) Finishing off an enemy nearby with very low health.
4) Quickly breaking blocks in the way of passing, such as in Graveyard levels and clockworks tunnels.

This would not hurt to add, and I am sure bombers would appreciate it. This is mostly PvE oriented, and in PVP Lockdown, bombers wouldn't want to get close enough to a sword-master or gunslinger to spam the low damage and short stun, but could give bombers just a bit of an edge in Lockdown as well.

Thanks for reading, feedback is appreciated.

TL;DR Bomb charge cancel animation can hit and break blocks.