Book printing is a bit off-topic...
I want there to be "magic for all occasions"... but a lot of it should be low level. Hallucinatory Terrain, for example, is perfect in a few situations... but does it need to be 3rd level just because it lasts?
I'm an unrepentant pack rat, because there's always that one time you need the thing you just got rid off (or the time you had the bizarre thing because you kept everything). Story from a previous edition: Reading the rulebooks, Snilloc's Snowball is a hard pass; Decastave, useless. Then I rolled up a low level wizard with Snowball, Magic Missile, decastave, obscurement (I think), and jump. And darned if I didn't use everything single one of those spells in that first session! I felt like a freaking genius, using these "inferior" spells (okay, MM isn't inferior, but it was only doing 2d4+2 damage at the time) to freeze a lock, hide from guards, be armed in a weapons-free town when a barfight broke out, etc.
If I had Hallucinatory Terrain, I'd be looking for nails to hit with that hammer. (And also hunting up a wizard to teach/sell me Fireball!)
In my campaign, the fighter who uses pikes has found 2 magic daggers, a magic warhammer, a magic javelin, and half dozen "special material" shortswords and daggers. He took his share of the loot, went to the town of Mariha (known across the Three Kingdoms for making the best pole-arms), and bought himself an exceptional (nonmagical +1) pike. Then he went to the provincial capital, and paid a wizard to enchant it for him. The fighter/rogue, meanwhile, had all those special material daggers melted down by some dwarves that owed him a favor, and got a nice special material longsword. and if they continue on the current path into the desert kingdom, they're going to come across lots of spears and scimitars... no pikes.
Likewise... the wizard finds spells that mattered to the (long-dead) mage who had them. Not (usually) the spells the player wants to find. Gravelkonk was an alchemist that desperately wanted to become a sorcerer, so his invented spells feature that; his partner, Slate, was a sorcerer who hated his sorcerer relatives, so his invented spells - thoughtfully recorded by Gravelkonk! - were very anti-caster. And they both had utility spells for living underground. Neither had Fly, or Cone of Cold, or Phantasmal Killer.... or even Tiny Hut!
I think spells need a revamp. I think damage spells need to be balanced - and I think situational use cases are a balancing feature, while recognizing that it is hard to quantify. There shouldn't be a 7th level spell doing the same or less damage than a 6th level upcast spell. (cough hand... sword cough). I also think elements and conceptual themes should remain distinct - acid behaves this way, lightning behaves that way, which should make those kinds of spells feel more unique from each other. (Just like I think weapons should feel distinct... another current 5e failing.)
So, sure, go ahead and drop completely redundant spells. I'm cool with upcasting giving new features. Illusion 1 is silent image, Illusion 2 is long-lasting or bigger image, and Illusion 3 is long-lasting, big image with sound. Phantasmal Killer is not Illusion 4, though! But don't drop niche spells... these reward the wizard for hainv searched them out (or found them), and carefully copied the into the spellbook, for exactly that time they have found that Soul Guardian who demands they stand inside running snowmelt (water breathing, resist cold) while picturing a field of springtime dasies so real it becomes real (hallucinatory terrain), and then defeating the avatar of winter (immune to all damage but radiant; spirit shroud). Rewarding research and recon, the wizard is perfectly prepared for this encounter... using spells he'd probably never otherwise prepare.