What are your favourite alternatives to the four classical elements and the five chinese elements?
I've been thinking about some pseudo-scientific system that uses the four fundamental forces as a basis for its elemental system, where "magicians" tap into one of the forces. Possibly in the context of an industrial early 20th century style setting.
Each force would be classified by range and intensity, as well as its connection to the other forces. The two short range forces being melee/touch only, whereas long range forces decay in power with the inverse of distance squared. The two weak forces are focused on fine control but can't generate power as easily and vice versa.
Gravity (long, weak) is affecting the curvature of space to manipulate gravitational forces, teleport or distort time.
EM (long, strong) covers electricity, magnetism, light, long range communication and more interestingly biology and chemistry.
Strong and weak interaction are a bit harder to categorize in terms of clear powers, but I'd imagine it as something like this:
Weak Force (short, weak) has radioactive decay, slow disruption, weakening of materials and transmutation (heavy elements to light elements). It's also very close to EM mechanically, so practitioners of one can often reach into the other field.
Strong Force (short, strong) gets adhesion, ultra-violent decomposition and transmutation of light to heavy elements. Has a marginal connection to EM and Weak Force, but is much rarer than the other three forces (mostly because you can't have too many people who can easily create nuclear explosions running around).
Unifying those forces would be the equivalent of creating a Philosopher's Stone/ Prima Materia in traditional alchemy.