After reviewing the fine HMR sourcebook which has just landed in my lap, besides heaping abundant praise upon the developer and the writers, top-quality stuff as usual, I am musing and wondering:
Reasoning from the assumption that any Mystery secret and any non-Hermetic magical secret ever published in any sourcebook does factually exist in the ArM setting, even if it's not yet known to the Order at large.
At the current state of magical advancement, it fairly safe to affirm that many, if not most, of the so-called Lesser Limits of Magic have been proved to be nothing more than limits of insight and development in the RAW flawed current state of Hermetic Theory.
The Limits of Aging, Arcane Connection, Creation, Energy, and Vis have all been definitely shown to be surpassable by the integration of the appropriate non-Hermetic magical insight. There is less definite but strong circumstantial evidence that to some degree this might also be true for the Limits of True Feeling and Warping as well.
In all likelihood, with the passing of decades and centuries, the Order shall eventually manage to incorporate pretty much any insight it can from non-Hermetic traditions, extinct or alive.
So I would wonder where such an advancement would leave the Order, and what about the remaining Lesser Limits (Infernal, Lunar Sphere, Soul, Time) ? Is there anything really, provably special about them, to think of them as aspects of the Greater Limits, or this assumption has been definitely discredited after having been proven wrong about 5/7 other Lesser Limits ?
And let's make a little thought experiment. Let's assume an Order, sometime undefined in the future, which has successfully integrated and spread the mystical insights from most non-Hermetic traditions. Nothing too world-changing, so let's assume that the Hermetic Breakthrough shall be eventually coming, but are still studied in the labs. Let's say the Order has mastered the following Discoveries:
Event Duration (Defixio magic) (Minor)
Fertility Ritual Magic (Fertility magic) (quasi-Major)
19 years Duration (Hyperborean magic) (Minor)
Hermetic Rune Magic (Vitkir magic) (Major)
Subtle Opening (Folk Witch magic) (Minor)
Ritual (Charged) Items (Folk Witch magic) (Major)
Cailleach (AKA Diedne) Magic (Gruagach magic) (Major)
Flexible Formulaic Magic Spell Mastery (Gruagach magic) (Minor)
Unaging (Gruagach magic) (Major)
Let's also assume that either Initation scripts to develop any of the above Virtues are widely available in the Order, or the second Major Breakthroughs to integrate them fully have been done as well. Bonisagi are still slavering day and night in their labs to unlock the secrets of Unlimited Range, Vis-less Permanent Spells, Energy Magic, and Improved Voice Range.
How all of this would change the Order magically, socially, culturally and in the daily life of a magus ? Which exotic supernatural abilities would magi typically choose to learn, in addition to the Hermetic Arts ? How often would they "breed" apprentices, and which traits would they choose ?