Some more impressions:
-The game is longer than five levels! Was glad to see another stage pop up after five. Dunno how many levels there are supposed to be. One level is an 8-bit version of the ship from the Ritual Of The Night demo!
-Levels have branching paths. Unsure if there's different bosses but it doesn't seem like based on the map previews between stages.
-The difficulty starts ramping up after the first stage and starts getting progressively-harder, mainly because of platforming sections where you have enemies flying at you (just like the medusa heads in 'Vania)
-You can switch between veteran and casual play modes after you get a game over or when starting the game. Veteran is old-school 'Vania, with a limited number of lives and you also get knocked back when hit, which makes platforming sections challenging. Casual gives you unlimited lives and you don't get knocked back, but as far as I can tell, that's it (?). You don't get penalized for using casual mode so I decided to switch to that for the rest of my initial playthrough, mainly because of some frustrating jumping sections.
-Characters: The main sword-guy is good for close-range combat. Miriam is good for farther range combat and jumps a bit higher. The Alucard rip-off is good for turning into a bat and flying, plus his normal attacks go at an upward arc which can really help (and also hurt- he can't hit some ground enemies). The old man is...old. His attack is slow and shitty. He's basically good for his Ninja Gaiden-style firewheel and that's about it. I used him to kill a certain boss where this power really helps and that was about it.
-When one character dies, that's it until the rest are dead. This can kind of suck if you need someone to get to an extra area or alternate path, or if you get stuck with only the old guy left.