I don't know that (spells that depend on HP) ever came up, in terms of spells that depended on such. Most of those spells were high-level spells that we never saw. The only one I can think of that actually saw use was Sleep, which was always a gamble anyway since you didn't know how much it would affect.
Good to know that low level 2e didn't have that. Low level D&D seems to be an entirely separate game from mid-level-plus. I almost wish that they stuck with only 10 levels in 5e. Yeah the internet backlash was fun to read, but sticking to ten levels would let them make the overall class design better and help them better focus the D&D brand's identity (versus the current brand of big-tent back-compatible whatever-sells Forgotten Realms brand).
D&D is not a game of subtleties. Just as it's incredibly obvious which class someone belongs to (if any), so it is also obvious what their alignment is - which is to say, anyone can tell by looking, unless you're specifically making an effort to hide it.
Your view of D&D is both alien and intruiging to me. Now I know how 4e Star Pact warlock feels

I'd like to play a psychologist in your campaign, and see how I can abuse it
[sblock]
>>A troubled NPC enters the Psych Office in Saelorn's world ...<<
NPC Patient: Doc, I'm stressed out. Can you help me?
PC Doctor: Sure.
>>The doctor grabs a stack of papers ...<<
Doctor: Look at these pictures and tell me "What class do you see?"
>>The doctor shows a picture of a human holding a sword<<
Patient: I see a fighter.
>>The doctor shows a picture of a human holding a bow<<
Patient: Uhh ... another fighter class, I guess.
>>The doctor shows a picture of an elf holding a bow<<
Patient: Uhh ... that's just an elf right? I mean, elf is a class right?
Doctor: Certainly.
>>The doctor shows a picture of Clark Kent wearing both his glasses and his superman jersey<<
Patient: Hmmm. That's tough.
Doctor: Take your time.
Patient: ...
Patient: I feel conflicted. Part of me wants to say Expert (Newsreporter), but I also want to say Fighter.
Doctor: Well, let's try another one.
>>The doctor shows a picture of Tarquin from Order of the Stick<<
Patient: Hmm. I'm still confused.
Doctor: Then let's try something else.
>>The doctor grabs another stack of papers ...<<
Doctor: Look at these pictures and tell me "What alignment do you see?"
>>The doctor shows a picture of a paladin<<
Patient: Lawful Good
>>The doctor shows a picture of Asmodeous<<
Patient: Lawful Evil
>>The doctor shows a picture of an elf<<
Patient: Chaotic Good.
Patient: Wait, can chaos ever be good? It's kinda shortsighted and unreliable to be chaotic. Does "chaotic good" even exist?
Doctor: It depends on who you ask.
>>The doctor shows a picture of a kender<<
Patient: Hmm. I'm not sure of alignment. But for some reason I'm feeling a little salty.
Doctor: Well, let's try another one.
>>The doctor shows a picture of Batman<<
Patient: ...
Patient: I don't know. I feel conflicted again.
Doctor: Hmm, this does seem a little concerning.
Patient: So what does it mean doc? Am I crazy?
Doctor: Well, the results are inconclusive.
Doctor: I know. How about I only charge you two gold for this session?
Doctor: You can take these pictures home and think about them.
Doctor: Then come back tomorrow if you are still feeling conflicted.
Patient: Okay.
>>The NPC pays and leaves<<
>>The doctor earns 500 XP<<
>>The doctor earns 2 gp<<
>>The doctor smiles and lights a cigar. He ponders the patient's responses, and awaits more gold to spend.<<
[/sblock]