That's homebrew. And a flavorful homebrew is extremely easy to do, so if it's about having a character have the core mechanics of a certain caster but all mundane in flavor, it can be homebrewed. Even if they can't be counterspelled or don't need components, it's not the most world-breaking homebrew.
Uh...no, I'm sorry, flavorful homebrew is NOT easy to do. In fact, it's EXTREMELY DIFFICULT, that's one of the biggest problems I have with 5e. It presents this idea of being easy but it's actually really really hard to make a new class or a new subclass. People will RIP into you for it being too weak or too strong. People will oppose
literally anything you do. I asked about PrCs, and was massively told "NO PrCs, those are HORRIBLE ROTTEN GARBAGE, just make it feats those are perfectly fine," except they
aren't fine, because whenever people talk about feats, SO DAMN MANY then immediately say how horrible and awful feats are and how the game should never have had them in the first place. And new
classes?
Fuggedaboutit. There's been a near-constant push since the D&D Next playtest to eliminate as many classes as possible; even the "core four" aren't immune.
It's hard to write effective, balanced homebrew. It's harder still to find people willing to usefully critique it, rather than simply shout it down as unnecessary or wrong-headed. And it's
damn near impossible to sell DMs on homebrew you find or make. The odds of actually getting to play homebrew you like are fantastically small unless you're already good friends with the DM, and
I don't have anyone like that. LOTS of people don't in this modern, internet-heavy D&D culture we now have.
But also, my point is that most players will be expected to use those rules and some may not enjoy that experience of being expected to do things. Every feature comes with the expectation of being used when it's the optimal choice in a party.
And...you know that this group is bigger than the group that's been frustrated by the caster/martial disparity for
literal decades...how, exactly?
Besides, you are
yet again talking about perfection--optimality, in this case--when
again that is NOT what I'm talking about. I'm not expecting Fighters to be "optimal" in non-combat situations. I just want them to have SOMETHING meaningful they can contribute. What that should be, I don't know. Rogues have things like Reliable Talent and Expertise which are very easy to use ("anything less than 10 is 10," "double your proficiency bonus") and require essentially no mental overhead. Why can't Fighters get something different (since I want classes to remain distinct) but comparable? That would go a ways to addressing the problem; I cannot say for sure that it would be enough, but it would be
something.
So that father of 3 who only opens the Rulebook when they level up can play alongside the hyper-focused rules lawyer and neither feel like they're handicapped when it really matters: when their characters might die.
Again: who said these options have to be complicated? Who said they have to come at the cost of "handicapping" characters in combat? And why are we designing rules for people who
don't even look at them?
I'm sorry but this is just ridiculous. We're now designing a game for people who don't actually want to play the things that the designers have explicitly said matter most. And we're
not designing it for the in principle
just as significant group of people who aren't interested in combats and just want intrigues, who don't think there
should be combat deaths or the like. It's all incredibly circular and just...really difficult to understand. We should bend the whole rest of the game--and snub all the many people who want Fighters that are enjoyable in
all of the things D&D is
explicitly designed to do--solely because a few people are
too busy to read the rules and (somehow, for ill-defined reasons) feel
weaker in combat because...they're able to do things that
aren't in combat...?
Perhaps this is a massive misunderstanding on my part, but I'm just...no. You have challenged whether it's worth pursuing this thing, and offered a
dramatically more niche alternative instead. Unless and until you can demonstrate to me that
at least two decades of people BITTERLY complaining about this problem is outweighed by the people who are so desperate to
avoid playing the other explicitly-essential parts of the game's design, I don't and won't buy it.