I can only really describe Kill no More as cliche in the best way possible. I'm actually not really a fan of cliches, tropes and whatnot which is why I put off KnM for so long after reading the first volume or so since it just seemed like tropes galore (cute, clumsy glasses girl; insanely powerful, calm and cool guy; uber-cheapskate). However, this series is so much more than that. The world is very well developed -- mecha, knights and magic simultanously exist in the same world (it sounds a bit like overkill but it is handled very smoothly); at the same time technology also plays a major part (eg. healing 'Maxuns'); magic is explained, not just assumed that it's just always existed. The plot, although not as focused as some of Yu Wo's other stuff (Legend of Sun Knight, No Hero) is coherent and still ties up loose ends. Seemingly insignificant details are worked into the story at later parts, which makes for a detailed, surprisingly complex reading experience.
What is really cool though, is the dynamic interaction between the characters. It's not a story about one character becoming super powerful and reaching their goals; it's about characters working together with one another and developing as a result of that, which is why I think the characters are so interesting to read about even though their individual characterisation might seem cliche.
So basically, go in with an open mind, and keep on reading past a few volumes.
(For fans of Yu Wo, I think this is definitely at least 10 times better than 1/2 Prince, about half as good as Legend of Sun Knight, No Hero and about 80% as good as Eclipse Hunter; at least 1000 times better than any other popular shounen though. 😀 )
Edit: The lightnovel is already up to vol.8 at this point, far further than the manga. You can read it at Japtem.