Circle of the Moon was a really solid little entry in the series I felt. After Symphony of the Night this first GBA title took much of the same fundamental ideas and applied them to a whip-wielding protagonist. I enjoyed that. I also found the challenge, the special abilities, the return of familiar tunes, and the new art style to be a welcomed change of pace. As for the dark graphics, I found them to be fitting for a Castlevania game. Palette-swapped sprites? I didn't think much of them when I was trying to fight my way through them. If anything, my only gripe was that the game could have used more variety. I mean, I enjoyed the added challenges of the additional modes, but I did wish for some reason at the time that I could have played through the game as Hugh. No big deal though.
HoD, on the other hand... That seemed to me like a failed attempt at continuing the Symphony trends, right down the Alucard-wannabe Belmont at our control. The colorful, eye-grabbing visuals were a distraction, the big bosses felt more like obstacles than opponentes, and the story just felt artificial. At least Circle's plot had a sense of urgency beneath its simpleness, and a touch of originality on the surface (I happen to be a fan of non-Belmonts de-throning Dracula). Juste's little jaunt through the castle felt bland by comparison, with the only bright spots being a truly unique musical score (screw the limited technology) and a much more interesting view on the inverted castle idea. The bottom line though? HoD was a straight-forward and highly unusual cakewalk compared to CotM.