mmm... you'll eventually get their personal reasons there. Waver at least you got from the beginning - he wants to prove himself. the three houses are the three houses (much of the same way they are in F/SN though Rin evolves). the Matou guy as you put it has a personal reason for fighting. Caster being the odd man out isn't that strange considering Caster was... also the odd man out in F/SN.
the relationships will become much clearer as the show continues. do think you'll like quite a few characters though.
oh i know what you mean. but overall the show's tone is demonstrative and not subjective like F/SN's, where against our will, we're forced behind shirou's misogynistic, brain-damaged, hero-complex eyes. because shirou didn't know anything, the process of learning and experiencing the HGW5 was organic and worked well. here, each character ostensibly has some motivations and some of them are even likably evil, but the stakes don't feel the same. it's just easier to relate to high school students (like waver) rather than these super-cold assassins, dead-on-the-inside church mongrels, weirdass serial killers, etc. these guys make for good combat and drama but not the best character-driven storytelling experience IMO
that said i am enjoying it quite a bit
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Je suis toujours serieux. D'autrefois, personne ne me penserait serieusement.