releasing feats that "deprive" existing classes of their uniqueness already exist. The fighter for example, is a pile of armor and weapons with a special die they get to spend. There are feats that do that. Ritual Casting Feats and the 1st level + Cantrip feats are also class imitation abilities.
But you can avoid copying a sorcerer and also enhance a sorcerer. For example, I created a feat that simply jacked the spell level. The sorcerer doesn't do that, they spend points. If you make a feat that gives the sorcerer more points, like + your Charisma bonus or +your proficiency bonus to your pool, that feat would literally only be friendly to sorcery metamagic.
the current metamagic list for the sorcerer is extremely small. Over the years, there were scores of metamagic feats added to the game. In fact there were meta magic metamagic feats!
Examples:
Metamagic Pool - convert spell slots into metamagic power
Metamagic Master - meta magic is easier/cheaper to cast
Multimetamagic - apply another metamagic to a single spell
The sorcerer doesn't need monopoly over the metamagic. The idea that the spell list of the wizard or their spell options per day empowers them with versatility beyond metamagic is a gross misreading of the wizard.
can sorcerers research new spells?
if the answer is no, then they can become the gods of metamagic, and that's fair.
if the answer is no, then there is really nothing special about the wizard at all.
Since the sorcerer and wizard have close to the same number of spells per day, the only thing you can really compare is their spell lists (a 1-5% difference in impact) and their special abilities (a 30-40% difference in impact). But the sorcerer is double stacked in this area. they get meta magic AND cheap bonus powers.
a level 20 sorcerer has
4/3/3/ 3/3/2 2/1/1
a level 20 wizard has
4/3/3/ 3/3/2 2/1//1
the sorcerer only knows 15 spells. And 6 cantrips. They can convert points and produce 3-7 additional spell castings.
the wizard is said to have learned 44 spells, prepared 25, and 5 cantrips
at 20th level a sorcerer gains 4 points, i.e. 1-2 spells back per short rest.
at 20th level a wizard gains 10 spell slots during a single and only short rest, totaling 2-10 spells.
In a given day, a character could achieve 8-10 short rests (and still dungeon crawl or travel 20+ miles), or 15 short rests in a down time scenario.
During that time, the total bonus spells a sorcerer will have is
minimum 11 spells +1 cantrip
maximum 37 spells +1 cantrip
During the same time, the total bonus spells a wizard will have is
minimum 2 spells + 0 bonus cantrips
maximum 10 spells + 0 bonus cantrips
In any given day, the Sorcerer casts more spells than the wizard. But spell choice? Well, truth be told, most wizards just cast the same bundle of spells over and all. Same is true for most caster classes. How many times have you seen firebolt, shatter, or fireball cast? Class optimization guides make it pretty plain you are lucky to see a dozen good spells in 9 levels. There's the transform spell, the destroy spell, the travel spell, and the defend spell. If you are a cleric there's also the heal spell and the bring back the dead spell. You might get bored and throw in the Control or Deceive spells. As a backup, you might have the Buff spell and the Alternative Damage type destroy spell.
Except, here's the thing:
Now, tradition has it that any spell a spell caster creates themselves, is automatically added to their list. Their list grows, it is not overwritten. You do not forget fireball because you spent 6 months creating your own version of lightning bolt. There's also a tradition that says if you failed to learn an existing spell, you could spell research it to CREATE an existing spell to add it to your list. So if you were too dumb to learn Fireball in your early life, you could set up a research lab in your golden years and "research" fireball to overcome that block. You were allowed to research ALL spells of your class this way. Additionally, you could research spells that were slightly outside your class at higher level, or with slight changes to fit your identity and theme. Necromancers got awfully close to Clerics in some ways, for example.
And there's the rub. The total number of known spells a Sorcerer can choose from is unlimited, just like a wizard. The wizard only gets a head start, but the Sorcerer retains their higher number of spell slots per day regardless of how many years they spent researching new copies/versions of existing spells.
