The one major issue I see with your draft is +1

per specialist for Tradition civic. Tradition is available very early, at Oration, and players should not be able to solve the problem of early city culture so easily. There are a number of options for early culture: Monuments, Theatres, Libraries, Stonehenge, an early religion, free Artist slots for Creative leaders, free specialist culture for Philosophical leaders. Each city must pick the option best suited to it. But +1

per specialist circumvents them all. Players need only adopt Tradition (there are no other Legal civics available so early anyway) and build Cemeteries. Monuments and Stonehenge become redundant; and Creative and Philosophical leaders lose their early game edge.
If nothing else, I would leave the Legal civics alone. Return +25%

to Tradition and +1

to Authoritarianism.
Here, then, is a counter-draft. It assumes the Legal civics are unchanged, and presupposes the following previous changes:
- Upkeep for Theocracy is reduced to Low.
- Agrarianism has a freestanding Health bonus and keeps the Farm commerce bonus.
- Upkeep for Industrialism is raised to High.
- Social Welfare removes the happiness penalty from Corporations.
- The trade route penalty for Redistribution is removed.
- Upkeep for Clan Warfare is raised to Medium.
- Warrior Code swaps the Great General bonus for increased happy from Barracks.
- Organized Religion and Free Religion are renamed Orthodoxy and Pluralism.
--- GOVERNMENT ---
Aristocracy
Requires Nobility
Medium Upkeep
• +1
from Orchard
• +1
per specialist (Optional)
• No maintenance costs from distance from palace
Confederation
Requires Guilds
Medium Upkeep
• +1
from Watermill
• +1

from Harbour
• No maintenance costs from number of cities
Democracy
Requires Politics
High Upkeep
• +1

from Village, Town
• +1
per specialist (Optional)
• +50%

I understand that you don't want to spread improvement bonuses too widely; but since Democracy strengthens Villages and Towns, I see no reason why Aristocracy and Confederation can't have flavour bonuses for some of the rarer improvements. Farm commerce was perhaps too much for Aristocracy but the Orchard works just as well, especially as it produces Wine. Players won't build enough Orchards or Watermills to affect their civic choices; those will depend on whether they prefer zero distance maintenance or zero number of cities maintenance. I still think those bonuses ought to be swapped, by the way. Empires with many overseas holdings (like the British Empire) should prefer Aristocracy and zero distance maintenance, as they leave colonial management to expatriate governors and admirals drawn from the upper classes. Empires that sprawl across single continents (like the Soviet Union) should prefer Confederacy and zero number of cities maintenance, as they organize into a federation, bound by treaties and overlapping political units: cities, regions, provinces, and territories. Well, it's your call.
A final point: if you want to limit specialist bonuses to two civic categories, they should probably be Legal and Religious. Altruism is a much better choice for +1

per specialist than Tradition, as I've explained above. So you can cut specialist bonuses from Government altogether (and lower the upkeep for Democracy to Medium) or you can retain those I've suggested.
--- ECONOMIC ---
Professionalism
Requires Artisanry
Medium Upkeep
• +1 trade route per city
• +1

from Workshop
• +2
from Market
Bureaucracy
Requires Civil Service
Medium Upkeep
• Unlimited Spies
• +100%

in Capital
• +1

from Lumbermill
Free Market
Requires Economics
High Upkeep
• Unlimited Merchants
• +50%

from trade routes
• +2
from Corporations
Environmentalism
Requires Ecology
Medium Upkeep
• Unlimited Scientists
• No

from Corporations
• +2

from Windmill, Nature Reserve, Marine Reserve
Extra health for Environmentalism is uninspired. Not only does it make the civic too health-focused, it has the unintended consequence of encouraging more pollution: the 5

neatly balances 5

from Factories and Industrial Parks. (There's no use in letting the extra health go to waste, after all.) If you don't like bonus food from Corporations, I suggest unlimited Scientists: environmentalism spurs greater research into ways of living within the limits of the natural world. I would also bump Free Market to High Upkeep. It's clearly the strongest civic in the column. It can be the "high cost, high reward" option: reap the rewards of corporate greed but expect significant corruption and the occasional depression.
--- MILITARY ---
Standing Army
Requires Logistics
High Upkeep
• New units receive +2 Experience Points
• +100% Great General emergence
• -50% upgrade cost for military units
I don't think this civic is too strong. If anything, I feel "+100% Great General emergence" is weaker than "+2

from Barracks." Extra happiness across the empire helps mitigate war-wariness and directly increases citizen productivity. By contrast, the first few Great Generals are useful but they steadily lose their value, especially as they cannot contribute to Golden Ages. (I think.) Ideally, I would replace the starting Militia civic with no war-wariness Clan Warfare, and use the extra slot for a new civic, "Mercenary," which would provide -50% upgrade costs and +100% gold from pillaging and capturing cities. But that must wait until 1.19.
--- RELIGIOUS ---
Altruism
Requires Ethics
Medium Upkeep
• +50%

in cities with State Religion
• +1
per specialist
Rationalism
Requires Scientific Method
Medium Upkeep
• +1
per specialist
• +2

from School
Altruism and Rationalism are more or less unchanged from 1.17. The specialist bonuses can be bumped back up to +2 if you decide not to keep their counterparts at Aristocracy and Democracy. With only two bonuses, Rationalism should probably remain at Medium Upkeep.