So, my pal @Marko_Markoko said to me he wants to find ways to bring OSR players over to Ars Magica
Ask, and you shall receive, because I have a new pre-hermetic, non-hermetic tradition 
It is based, once again on the Touched by (realm) (CG71) and Wondrous items rules ( C&g p72-73), as well as the Wordsmith rules ( TCI p117-118): You have a Craft Spells, or Use Magic Ability, which you can use to create/learn " spells" as per C&G, with several differences:
- You create effects using Int + Use Magic + Aura+ bonuses as per Wordsmiths ( TCI p 117)
- R/D/T are free, although limited to to total of +3
- You can include penetration, as per the standard rules for Enchanted items. This adds the chosen Penetration to the effect's Magnitude.
- Such spells ( or, rather, enchantments), when crafted, must include a triggering action ( gesture and/or word), which is mandatory
- You may have Ritual effects, these are only effective if you have correct vis at hand when activating the effect ( 1 pawn/ 5 magnitudes, as usual)
- Not having a physical anchor, they decay other time. Typically, if you can't maintain you attention on them ( such as if you're sleeping or unconscious), they lose one " use" after a number of hours equal to the effect's Magnitude ( not including penetration). If you're awake but otherwise occupied, they lose one "use" every 2 hours. These are cumulative: 4 hours awake and 1 hour unconscious count as 3 " spell decay" hours. To prevent that, you can perform a short ceremony to "refresh" your spells: this takes 5 minutes per magnitude of the effect + 5 minutes / 10 penetration (round up).
- If you have used up spell " slots" ( ie, cast them, or lost them due to spell decay), you can regain them by intoning lenghty incantations, which take 15 minutes per (magnitude of the effect + Penetration/10 penetration, rounded up) for each use.
- Penetration is affected by the local Aura when expending a charge.
So, there you are, OSR-style spellcasters who spend time " putting their spells into their grimoires", and need to " commit them to memory" regularly
If you want different styles of Spellcasting, you can either restrict the forms one has acces to and / or change the Aura from Magic to Faerie and/or change the name of the skill used,as well as the ability.
=> you could have " Magicians", using Int+"Craft Spells" ability, attuned to Magic Auras, having access to the Elemental forms, "Druids" which use Pre + "Nature's Ally", attuned to Faerie Auras, having access to Herbam, Animal, MuCo ( limited to shapeshift, and " Animal improvement " spells, like " Eyes of the Cat", maaaybe some Auram ( winds only) and/or Terram ( Earth Only); "Clerics" using Com + "Prayer" ability, attuned to Divine Auras, having access to Corpus, Mentem and Vim. Tailor as per your group. I can always do more / detail more, if you ask me.
Likewise, you may tailor the vis to each group, from " A dragon's heart" to " sanctified water / holy symbol (use the rules for extracting vis, using Prayer) or "a branch from a centuries old Living Tree"
Hope you find this fun , and, especially, that you find some use for it 
