I guess as a result of being basically F/SN fanfic, it had the same sort of flaws but more glaring. Cast bloat, wonky characterization (idealistic motivations portrayed poorly, melodrama, etc), chuuni to the point of self-indulgence, etc. Some of them were fun to watch though and the animation blowouts at a few points were neat. I didn't hate it but the Jeanne/Sieg combo is definitely the weak link.
It's both a good and bad thing, but what you also see with both this and especially now with GO is that they cast about as wide a net as possible in terms of character appeal in order to sell it. You've got something for the purityfags, the arafags, the lolifags, the fujoshits, the tomboyfags, everything.