Your suggested removal of multiplying work in addition to adding guidelines to interact with RoP:M/F aura rules would give the virtue a sort of purpose, that seems like a good direction for houseruling.
I've still been absurdly busy with holiday aftermath etc, but the workflow I've devised so far is a mix of the Sacred Architecture [SA] workflow and existing HA workflow. The HA workflow is:
1) Devise Enchantment [Int+Geometry+Bonuses] vs [6 + Target Size] threshold check 0 Seasons
2) Open Devices (Labwork) Spend [Material X Size[sup]2[/sup]] pawns [Size] Seasons Minimum
3) Enchant Devices (Labwork) Spend normal vis for enchanting [Size] Seasons Minimum
4) Finish Enchantment [MuVi casting score] vs [highest enchantment +5-15] 0 Seasons
The SA workflow is divided for the three types of project, but are basically of this form with slightly different modifiers Aura Aspects (Adding virtues to auras)
1) Design Project [Int+SA+MT+Mu+Vi+Bonuses] vs [Based on Project] 1 Season
2) Build Project [Per+Craft+Aura+Stress] vs [Project level]* Variable Seasons
3) Implement Project Success Threshold in 2 per season to level aspect Variable Seasons
4) Upkeep project^ Aspect decays if you don't spend time on it Variable Seasons
(1 season can last years)
*This is checked at the end of the crafting and is kept for further use
^Only Aspecting an aura requires upkeep
So, there are a few big differences between SA and HA, some of which are a result of the overall different expectations. Notably, SA requires no vis but requires a lot more mundane effort to construct and upkeep the sacred building. there are similarities: First there is a design step ability gate, you check if you can even design the effect and stop if you cannot. Next there is are labwork-type steps, where you check your score against a target, note down how much your score beats the threshold and continue until your points equal the level of the effect. Last there's some kind of implementation or upkeep step that requires expending resources, vis in Bind the Mystic Structure and mundane effort in SA.
Text I have so far for Revised Hermetic Architecture [RHA]. It's still quite rough and needs refining, and I need to put hard thought to the guidelines.
Revised Hermetic Architecture governs three major techniques utilizing grand construction projects known as Edifices:
The art of creating Aura tethers
The art of modfying Auras
The art of enchanting Auras
This virtue requires Hermetic Geometry, and edifices must be constructed in a way that qualifes for the bonuses of Hermetic Geometry - but the benefits of those bonuses apply to Lab and Ritual totals. Arithmetic Book Bonuses apply to Lab Totals and mystery rituals if the book can be consulted. Calculations within this mystery use Artes Liberales (Geometry).
Made up of component parts arranged in auspicious ways within an aura. Often these take the form of an auspicious structure, but can also be several discrete small installations in auspicious places, such as a ring of stones arranged in astrologically significant locations around a sacred grove.
My workflow for Revised Hermetic Architecture [RHA], for the moment at least, is below.
1) Devise Edifice [Int+Geo+MT+Bonuses] vs [6 + Target Size + Aura Strength] 0 Seasons
2) Construct Components Standard Labwork for effects*, vis cost Variable Seasons
3) Bind Edifice Bind the Mystic Structure, vis cost. Do NOT need to learn. 0 Seasons
4) Integrate Edifice (? Certainly on Tethering) Variable Seasons
*This works differently than regular enchanting
[Int + Artes Liberales (Geometry) + MT + bonuses] vs [6 + Target Size + Aura Strength] to devise edifice. Target can be a structure or an entire aura: You do not need to target the entire aura, but you may. Standard full Aura is size 8. Numerology Book bonuses apply, +1 for consulting an craftsman with a 5+ in the primary form of the edifice. Will need [Size] components. The form is typically a building with auspicious icons and architecture (cathedral/temple) or a series of monuments arranged in a magical way (ring of standing stones).
This is a mystery activity and therefore only those party to the mystery understand lab texts produced. All of the component devices are enchanted at once during this mystery activity! Also notably: Bonuses to opening devices or spending vis on enchantments do not apply but bonuses to lab totals for enchanting items do apply.
Calculate effect level via guideline table (TBA). +1 level for every required device to complete edifice.
[Int + MT + Geometry + Creo/Muto/Rego + Vim + lab bonuses] for lab total, accrue points over the effect to complete (as regular invention/enchantment). Must spend pawns total over the process as if to open target boundary (SizeXMaterial). May experiment, with the usual benefits and risks. In other words, even if you have double the effect level in lab total (completing the mystery enchantment over one season), if you cannot handle that much vis in one season you must take more time to perform the mystery enchantment.
Arrange the Edifice components as set out during the Devise Step, placing them auspiciously into a magical structure. This CAN just be comprised of the Edifice components, but usually includes a mundane construction project to house the components. For outdoor components, a version of Hiding the Mystic Key is used to protect the components from the elements.
Cast a Binding the Mystic Structure ritual as described in HA. You need spend time learning this ritual, devising the precise ritual required is part of the Devise calculation and the secrets of this Mystery. You simply must be able to cast a properly powerful ritual and have the vis to do so.
I'm still toying with this idea, basically a version of SA's slow onset effects. It makes sense for me that the effects of this virtue should take a little while to come into effect, as the Edifice's influence propagates out into the aura. At any rate, it should not take meaningful additional resources beyond protecting the edifice from undue harm or disruption. That way, you can't use this virtue to whipcrack effects back and forth to optimize it (I.E. Aspect it to Muto for research on a muto effect, aspect it to Rego the next season for a new lab project and so on). I think I'm just going to have it be a flat effect that charges up a magnitude per season or so on. Might limit it to some of the effects in specific. Will circle back around to this once the guidelines are roughed.
Step 1: Adds MT and Geo bonuses, but adds aura strength to the ease factor.
Step 2: Enchanting the components is a mystery activity and is dramatically cheaper and easier because you do it all at once. On the other hand, it's harder to hyper optimize this step. However, there aren't rules for regular enchantments in this virtue - you can only use it for the special aura guidelines. Not sure how I feel about that, perhaps another minor virtue allows it, or I can jigger this slightly to allow enchanting an aura (as in, causing an aura to become an enchanted object).
Step 3: It's explicit that you need not learn Bind the Mystic Structure. Just another scores gate, but this one you can Wizards Communion or spend extra vis or whatever to cast it (and get ceremonial bonuses and so on).
What I'm going to do tonight is work backwards from some example mages of varying power (Average, Strong, Archmagus) and what they can reasonably cast, and devise guidelines based on those assumptions.