To explain the full reason why I've given such a high rating to an anime that - for all intents and purposes - is just an introductory arc is hard to explain without actually seeing it, knowing the author's work and their way of doing things, but I'll give it a shot and without spoiling things.
One constant throughout Hiro Mashima's writing is the 'journey adventure' that comes along for a hero or heroine who is then swept up in it, we got that with Groove Adventure Rave with Haru and we got it with Lucy in Fairy Tail, both are people who actively seek out adventure and are brought into a larger world.
So It's a shock when we get a hero this time around who is the reluctant hero, Shiki is a guy who likes his life and doesn't want change but has it forced on him due to loving people around him and that's the first thing I thought was both interesting and different for a Mashima work - and I like it.
Add to that the idea of sentience in robots being a constant and you've got a pretty amazing beginning for a story.
I won't go into other characters dynamics and their lives as it's spoiler territory but surprisingly this one is a little darker for a Hiro Mashima penned piece and I'm interested in that, the plots that are just beginning to be uncovered and the family dynamic built.
I stayed away for too long too as I wasn't sure whether it was linked to his other works - and it is tangentially - but it's still good, definitely interesting and I'm waiting season 2.
