Currently, it seems like any character, regardless of level, has a maximum of 6 0th level spells (For a given caster type).
However, these same characters can easily end up with double that number in 1st or 2nd level spell slots (particularly with bonus spell items - which never boost 0th level spells.)
In newer editions, the 0th spells are castable for free (slot in what you want and get infinite), due to their very minor or RP nature that lets a caster feel more caster-like for things like simple-attacks. The spells available at that level are not really that threatening in bulk, and not infrequently available from items that permit infinite use (Light, Ray of Frost, Magic Missile (1st level spell on a staff), Electric Loop (a 2nd level evocation on a staff)).
Even if infinite cantrips/orisons were impractical to permit (since I imagine overriding the standard spell-consimption hooks is not trivial), even increasing the available slots for higher level casters (either increasing the base limits, adding 0th-level spell slot items, or doing something like each other bonus slot gives another 0th-level) would permit more flexibility with what are basically a set of mundane utility and RP slots.
This is trivially accomplished by adjusting the values in the 2das.
Thoughts, Comments, Concerns please.
Cheers,
Kit