That's my problem too. So far, it sounds as though they're offering Manga-style releases of content that people can already easily obtain from other countries. I think it's good to get as much content brought over to the UK for people who cannot/won't import, of course, and no doubt we'll end up getting lower prices out of the deal (and possibly faster turnarounds if this means fewer complexities for Jerome and his team to wrangle with behind the scenes), but if I ask myself what Animatsu is likely to do for me, right now the only answer I'm getting is 'nothing'.
From the perspective of someone who only buys UK releases, I appreciate that things look very different and having a new version of Manga UK with more freedom to react to fan demand is a very positive move. Perhaps they'll surprise me and start adding more value for UK customers too, like Anime Limited do with their super-speedy releases and premium editions to compete with international offerings.
(I never even knew Halo Nightfall existed before this thread, let alone that information on their products was already out there.)
R