I think it's interesting to view this in reverse - in many ways it's like taking the existing cantrip system but allowing the option to "burn" the use of that cantrip for the day to up it by 1d of damage
It removes the cantrip subsystem and makes them all regular spells. They are no longer at-will abilities with their own subset of rules. They are now something that function like a regular spell for learning them, for casting them, and allows them to scale like any spell might rather than automatically.I don't understand the consequences.
You are first turning cantrips into 1st-level spells. Then you allow some of the 1st-level spells to be cast at will for reduced effects (although I can't check now, if the reduced effects are the same as the original cantrips or less).
Overall I don't understand what really changes, besides being a formal rearrangement of the system and minor changes to some specific spells. Spellcasters still have the option to cast at-will their weakest spells, spells still scale, it doesn't change the big picture enough IMHO to have a noticeable effect on the game (althought it might be a fun exercise by itself).
It looked to me, Li, that Sadrik is providing the option of casting cantrips at higher levels, in exchange for emptying that spell slot once cast, versus unlimited casting.
I would go with Remove Cantrips though. No one's mentioned the elephant in the room: anyone who can cast a weak spell, for unlimited times, is a priceless resource. Just think - hook up a wizard who knows Shocking Grasp to one end of a power line in Eberron (or anywhere, really), and you have a power supply that runs on porridge (and threats). A first-level wizard is much easier to coerce than a powerful elemental, right?
Casting magic being a world changer because magic is a world changer is the most nonsense I've ever heard. Take Firebolt: oh no, the wizard can consistantly do less damage than the melee classes, such a game changer. Or Mend. Now that magic can fix stuff with no expenditure the world shall enter a new golden age!
No. World changers are based on effects, not the name given to the system that delivers them.