Successful build - Chance fights ever on the side of the prudent.

Link to build: https://jenkins.wildfiregames.com/job/docker-differential/1879/display/redirect

Isn't the idea of a wonder that it heals extremely quick (as the former tooltips describe)? Thus a rate of 8 would seem more appropriate?

4 health per second is 4× as higher as garrisoning units in barracks after researching heal_barracks.json and 8× as high as idle organic units regenerating after researching health_regen_units.json, so I would say it's quite quick. The higher the number, the easier the wonder is to defend (kill some nearby enemies, garrison your wounded soldiers before they're killed, wait some seconds to heal them, send them back to the fight, repeat).
I chose 4 as a compromise between the six wonders that heal at 1 and the seven that heal at 8; actually 5 would be closer to the average. That said, I don't have strong feelings on the exact value chosen, so alternative opinions are welcome.
What matters to me is that wonders are equivalent; having one civ's significantly better than another is not really “fair”, especially in wonder victory games.

Method:
I am a bit worried about the procedure of how the resulting patch is determined.

Currently seven wonders have a healing aura and heal garrisoned units at 8 health per second, whereas the other six wonders heal them at only 1 health per second.

This statement is reproducible by reading the code.

Test Plan: Agree this is an improvement.

This is not a process that can be applied to the patch to least subjectively determine its correctness.

There is no good explanation for this

There is.
From the description, it seems you didn't find a reason and concluded that there is no reason.
But I remember there being a reason as to why wonders have more and others less healing.
I can find it in the irclogs, perhaps it could also be found in the commits or trac.
So the reason why the reason behind the numbers hasn't been found is because it's too hard to search through the media perhaps, and the irclogs should become more searchable.
But actually the reasoning is also represented in the name of the file deleted in this patch (actually the patch removes only the references, not the file. I see there is still the apparently unused hellenic_epic_temple.xml).
The wonders that are temples have the epic healing aura and there were people putting thought into it (regardless of whether that was a perfect thought).
I find only one wonder that has the wrong BuffHeal according to the reasoning behind the difference. (Hieron tou Apollōnos Pythiou according to https://wildfiregames.com/forum/index.php?/topic/25268-specific-name-review-structures/page/3/&tab=comments#comment-378978 ?)
If there actually has been an intentional reason as to why the numbers are the way they are found, and this patch removes this reason, then it should be shown why the reason was not valid.
If the idea is that "standardizing" is a good thing in itself, then this may conflict with one of the core game design principles (https://trac.wildfiregames.com/wiki/0AD_The_Vision#HeartandSoulof0A.D.) that each civilization plays uniquely. If everything becomes standardized, the civs become less and less unique.
So it seems right to remove inconsistencies if there has been no intent or no valid intent behind having the inconsistencies while actually fostering inconsistencies that are sound historically, gameplay-design and balancing wise.

Balancing:

and the factor eight difference is highly unbalanced.

Maybe, but just averaging the numbers may not account for the other imbalances that the wonders do or should have.

This patch gives all wonders the same value of 4 health per second (for comparison, temples heal units at 3 health per second).

Perhaps the number is meant to make the wonder more useful than only to gain more population.
If the numbers are equal, then it can incentivize the player to just build a new temple in place instead of moving all the way to the wonder after a long fight.
Another consequences of accumulating power at the wonder is to give the defender at his very center of the city (wonder) a boost, shaping more of an final/end-battle at that place.

The wonders that are temples have the epic healing aura and there were people putting thought into it (regardless of whether that was a perfect thought).

Actually all wonders are temple complexes, including those that currently lack that aura:

• Stonehenge (gaul) is a pre-Celtic religious site (from the Third Millennium)
• Cancho Roano (iber) is a Tartessian religious site
• The Great Stupa (maur) is a major Indian religious building
• The Hanging Gardens of Babylon (pers) an actor is clearly inspired by Mesopotamian ziggurats (the small room on top is the shrine that housed the statue of the deity)
• The Temple of the Pythian Apollo (sele) is based on a large sanctuary near the Syrian Tetrapolis (Antioch, Laodiceia, Apameia, Seleucia in Pieria), the core of the Seleucid Empire

So it seems right to remove inconsistencies if there has been no intent or no valid intent behind having the inconsistencies while actually fostering inconsistencies that are sound historically, gameplay-design and balancing wise.

That I fully agree with. (Hence this patch.)

Perhaps the number is meant to make the wonder more useful than only to gain more population.
If the numbers are equal, then it can incentivize the player to just build a new temple in place instead of moving all the way to the wonder after a long fight.
Another consequences of accumulating power at the wonder is to give the defender at his very center of the city (wonder) a boost, shaping more of an final/end-battle at that place.

As I wrote earlier:

The higher the number, the easier the wonder is to defend (kill some nearby enemies, garrison your wounded soldiers before they're killed, wait some seconds to heal them, send them back to the fight, repeat).
[...] That said, I don't have strong feelings on the exact value chosen

Successful build - Chance fights ever on the side of the prudent.

Link to build: https://jenkins.wildfiregames.com/job/docker-differential/1938/display/redirect

By clicking “Accept Revision” you imply you not only approve of the principle, but also of the proposed garrison heal value (5) and the presence of the epic_temple_heal aura.

Maybe like to see the wonders generating resources per second (other patch), I think it would be one more reason to build wonders.

Actually wonders already have a resource trickle, see lines 72--80.

Actually wonders already have a resource trickle, see lines 72--80.

Sorry, I had forgotten this, perhaps because the value of the generation of resources is very low in my opinion.

By clicking “Accept Revision” you imply you not only approve of the principle, but also of the proposed garrison heal value (5) and the presence of the epic_temple_heal aura.

Yes, i know. I have something similar in my mods, so i agree.

Yes, i know. I have something similar in my mods, so i agree.

Thanks for the confirmation, I was just checking.