I like the new art, old Melty Blood is a little to jagged and pixel-y for my taste, but that's just an issue alot of 2010 anime fighters have, where they opt to occasionally up rez the sprites rather than redraw them, older fans find it charming, everyone else not so much (same thing happen with Arcana Heart 3)
as for the new character designs, I have no attachment to the old designs so I can't really comment
as for the new character designs, I have no attachment to the old designs so I can't really comment