I will show you how to discover a story idea, by exploring what you 'know', and trying to find what is implied or missing.
What you know
I will make up some vague 'rules' suggested by your question. You will have more knowledge of your world so you will come up with different parameters.
- magic exists, some people are more magical than others.
- there are cultural/ethnic traditions to how magic is taught/practiced.
- there are pros and cons to each tradition
Hand Casting
People who do not need a staff or a ritual to do magic, just their hands.
Suggests people who had their magical props stripped from them and learned to do without. Possibly nomads who are pushed off their territory, or were enslaved for a few centuries.
Extrapolating from archetypes (or stereotypes) these people have proud history of continuing their traditions in defiance of ethnic oppression. Many voices and regional 'flavors' in the technique, shared informally through social gatherings. Might be matriarchal through families. Might involve music, and certain labors where an instrument/tool can be a surrogate staff.
Might be associated with gambling and thieving and sexual assault – vices which are stereotyped to underclass morality. This untrustworthy reputation effects everyone of their ethnicity since anyone can be scapegoated for hiding a magic ability.
Staff Casting
Feels like the diametric opposite to everything above.
Nothing more conspicuous than carrying around a big stick announcing you are a Very Important Person indeed. And when they get together, someone has the biggest stick. I'm expecting mages who are extremely hierarchical, probably rigid in tradition and 'legitimacy' – however that is determined.
I'd also expect this can be backed up with actual power. The bigger the staff, the bigger the wallop. Hence, not a lot of dissent within the ranks because the hierarchy is well understood by all. Centrally organized, might be patriarchal.
Extrapolating from organized religion, they are a political force. Any scandals involve abuse of power and/or accumulation of wealth. With wealth and power come creature comforts, nepotism in high places, and henchmen that can 'take care of things'.
Ritual Casting
I don't know what 'ritual' means in this context. It is either endless research into the merits of esoteric minutia..., or interpretive dance with costumes – so I'll make it both.
Ritual is a wide tent that includes many philosophies and sciences, but also art and self-expression and (depending on your level of society) psychology and social popularity. Might have many 'schools' that teach multiple traditions. Despite the focus on history and tradition, they can also be unorthodox and experimental. Education is valued.
I suggest that their 'prop' might manifest through craft or invention, an heirloom or religious symbol. There is something personal to it, and how they fit into the world. Some are grounded in herbology and medicine, some are empathy-soaking divas with a Vegas entourage.
Most likely to be middle-class, boojie, or nouveau riche. Power shifts with popularity. Might be politically independent or neutral. Might have a reputation for vanity/insecurity and self-interest, Might actually be kookoo.
What's Missing?
Now comes the real challenge. What was left out?
If you were to arrange them in a 2x2 grid, and assign a polarizing description to each row and column, what could fit in the fourth position (if anything)?
|
self-determined |
collective-minded |
| hidden/secretive |
Hand |
??? |
| exhibitive |
Ritual |
Staff |
These categories aren't real because I don't know your magic system or the details of your story. This grid is one way to differentiate and solidify how they are alike and different in very fundamental (polarizing) ways.
It should bring up compatibilities and ideological objections between these factions. If there is a fourth 'type' that is a bonus that can appear late in your story, or as an anomaly or (as suggested above) a secret collective that is revealed later.