AnotherGuy
Hero
Totally agree, which is why I have begun creating my own version of 5e.Nerfing casters in any significant way is not going to come from WotC; they've proven that through the playtest. Doing it through 3pp and homebrew is the only way, and the bigger the change you want to make to the magic system, the more likely you need to change the architecture, resulting in a compatible but different 5e, like Level Up or Tales of the Valiant.
With regards to looking at changes in magic...I think one needs to begin smallHow you nerf magic is also very important. A lot of people are satisfied with what casters are capable of, or it would have been changed a while ago (just not a lot of people here). When 4e leveled the playing field for everyone, for example, it quickly showed those who liked the general shape of what we had before and those who didn't. This may not be a large concern for this discussion, since I've perceived a strong overlap between those who want a mythic martial and those who preferred 4e to other forms of D&D, but you never know.
As in how does the spellcasting of magic work for the various casters and their categories of magic?
What may be used as an Arcane Focus or a Divine Symbol? Are there limitations?
Who can use an Arcane Focus? And why?
How is an Arcane Focus handled?
What are the benefits or drawbacks of using material components?
How many hands free are needed to do S and handle M or an Arcane Focus? And work through examples, particularly during combat to determine action economy.
Can a spellcaster be disarmed from material components or a spell focus?
Can a spell focus be sundered and what is needed?
How does one limit a spellcaster from casting without the use of magic-dampening cuffs?
Casting with shackles, can one make a Sleight of Hand skill check?
Metal gauntlets, how does that restrict, if at all, S components?
Spellbooks, scrolls...etc
These are the questions I tackled first as I needed to initially understand how magic is harnessed and how spellcasting works in the world I had imagined (forget WotC's rubbished rules) before I would look at larger things within the game.