So after playing a couple days of Blast Network, it's pretty obvious to me what the biggest design flaw in the game is. Other "bombing games" that shall be remain nameless have the advantage of having their play engine optimized and designed for this type of play. It's easy for them to program and create a grid system specifically adjusted for this kind of play. But Blast Network has to be based around the Spiral Knights game engine and therefore can only emulate a perfect grid system.

OOO has done a reasonable job in creating the grid for this kind of play, but there's one problem with their current implementation. Even though a player can have something like 90% of their character within a safe square, if even a little portion of their body is inside a square where a bomb is exploding, they will get killed. This means players really have to be mindful of never having a little bit of their character in an unsafe square, which can be difficult when things are more hectic. Here's a few diagrams to illustrate the point.

First, here's a mock closeup of a play grid.
http://i.imgur.com/EYU67.gif

Now, let's say a player has placed two bombs. The dark red area represents the bombs, where the lighter red represents the potential blast zone. Anything that touches the red will die.
http://i.imgur.com/Jz5de.gif

There's a few safe zones where a player can go. Often, players will tuck themselves behind a barrier so the two bombs explode to either side of them. The green square represents a player.
http://i.imgur.com/upky2.gif

But if things are getting a little hectic or a player isn't careful, they can have most of their body inside of the safe square, but might have a small portion outside of it. They will die.
http://i.imgur.com/tzu2m.gif

The solution is to slightly reduce how much the blast zone of a bomb fills each tile of the play field. This should give players a little more leeway in hiding in safe squares. This player has their body partway into an unsafe square. But since most of their body is within a safe square, they will be safe from the blast.
http://i.imgur.com/1Ak29.gif

I certainly know that I've had what I've felt are unfair deaths while playing the game just because my character was a mere pixel off into an unsafe square, when clearly I'm occupying a square that should be safe. Reducing the hitbox of bombs should do enough to help prevent a lot of these unfair deaths.