A refreshing departure from most similarly themed manga, I've read before. There are just too many shounen and seinen which attempt to tackle such storylines like "saving the world" but in the most annoying fashion possible. As in: endless fighting, horrendous characterization, "textbook psychology", over-drama, endless conspiracies that rely on one too many rather obvious coincidences, etc.
Well, in Biscuit Hammer, less is more. And although much of the plot is rather cliched and often too ridiculous to be taken seriously, there is a lot of depth: strong characterisation, implied thoughts and relations, layers upon layers of emotions and motivations that are subtle and not "in your face". In short, there is nothing pretensive that tries to take on too much than it can chew and thus the plot does not appear contradictory or overtly contrived.
And as mentioned, the cast is quite huge but like many other titles that work by establishing immense layers of plot and writing like 7 seeds, Music of Marie, Koori no Mamono no Monogatari, Bokurano, Yokohama Kaidashi Kikou and so on, you just cannot build a massive world without having enough characters to fill it with. Otherwise, such an ambitious story would feel empty and incomplete.
The plot itself is fun and because it doesn't always take itself too seriously, there's a very strong flavour of subtle humour. Instead of terrible gags, you get to chuckle and laugh when the various characters behave unexpectedly and light-heartedly. As a result, even though there is tragedy, those tragic moments truly do not over-burden the plot but instead, are touching. And thus, we're spared from over-sappy moments that might have turned the story into some soap opera, in the hands of a lesser writer.
Also, there is a very strong slice-of-life feel that to me, seems more common in yaoi manga, than in any other genres, that have such storylines and in Hoshi no Samidare, both the action and slife-of-life are well balanced-out. When the pacing changes, the writing does not drop in terms of standard and quality. And also, the "slice of life" ties the characters better into the plot because reading about their daily life means that the characters have even better reasons for their actions, thoughts and motivations. In a lot of action stories, you don't always get to really understand why the cast is doing this and that, only flashbacks and bits and pieces of their daily lives. Even more important, everyone seems more human with concrete reasons for "wanting to live and protect others and themselves" instead of being portrayed as "fighting machines" whose goals are to commit as much destruction and bloodshed as possible.
The art, btw, is quite good and it is very fitting for the story and its content. It's very expressive and excellent at depicting the characters' thoughts, emotions and their actions. Truly, this is an artist whose lines gently and subtly invoke emotions.
Now, what it could have done without: all those "panty flashing" moments, though few, were a bit bothersome though I am now used to it. Now, I'm no prude but fanservice is often bland and sterile, since it's not even stylish sexuality or anything interesting.