Some Doubts and House rules (PX and Speciality)

Hi, I have so ideas don't really breaking of the game but yes littles helps about experience and specialities.
First: You can describe a Spell or other Lab Text how fount of Exposition of some Abilities, like "Scrying Pool" for Magic Lore, or Spells thinked against supernatural beings. Craft Magic spells of course works like Exposition for that differents craft Abilities. And so over, the Core Rules let that but i like write that things in the Lab texts.
Second: Some Hermetics books and lab text can work like Sources for others Supernatural Abilities fi the Writer had that capabilities and intention (Breacktrought and Insight fount of course too). For Example a Book that is two Summae that have the matter of Muto and Terram can work like a Summa1/3 level of the others two Summas for Mythic Alchemy, and since any Magi couldn't learn for penalties is a good story hook. So, the idea came for the Elementalist Forms Books for Hermetics and Hermetics can do they for Elementalists.
Third: That a Character could change Speciality after learn from other with that Speciality and win Experience Points sufficents for incresize the Score. And of course afer a great adventure taht could change perspective and was important for the character too and really related for the Ability, for example a long Tribunal discussion to grow up the Ability of Code of Hermes and change the speciality form "Apprentices Rights" to "Peripheral Contracts" or similar event.
Fourth: Realms Lore related to Auras Score where can spend Practice time. So... a Supernatural Nuissance and similar problems could occur if the wizard want learn aboaut his Supernatural enemies in their territory, je.

For Experience doubts...
Supernatural abilities in Magi selected with their Virtue when you are creating them are considered favored abilities or do they penalizes the Source quality?
In that case, Can they be practiced?, or can they grow by exposition?
Does Twilight good experience need the meditation and calm abaout all the season after? Is this affected if the Warping adn Botch was for other supernatural ability, Do use the Twilight experience for grow?

Thanks for your helps.

Leaving the house rules to the side, lets talk about your experience questions. First, once you get the virtue (by starting with it, Twilight, Mystery Cult, etc.) there is no penalty. The ability is now "favored". If you "learn" something in Twilight, you know it when you come out. The time in Twilight is the only time needed to understand. Twilight is what happens to Hermetic Mages. The source of the Warping doesn't matter. Supernatural Ability, Botched Spell, Original Research, Infernal or Divine Warping, etc. Two Warping points at one time, check for Twilight. I hope this helps!

Two ideas that i did't write they because i forgot it is that:
Fifth: The Supernatural aura can be a base practice quality source if you have Supernatural abilities to the supernatural aura in the training area. Since Magi and others hedge wizardas make a stress roll + aura studing vis is possible, but since they get more than the aura they needs get new higher auras with they get the ability great that the ability.
Sixth: No Art practice can get mor quality spending fatigue levels up to 8. That is the effort. Or maybe a absortion roll against the quality final of the practice season, and and if you fail, you lose a long fatigue level. A botch can drop the quality and too the lost of the same fatigue levels and wounds.