Go show me a civic in Civ4 or FFH which does anything like +20% commerce. Theres not even one that does 20% beakers. There is a reason for this.
Several civics in BtS are much stronger that that. Free Speech in a CE gives a 40% boost to commerce from cottages (+2 on the base of 5) and they are by far the major source of commrce in a CE, it typically raises commerce by 30% overall since trade routes are weaker in BtS. Nationhood is situationally the strongest civic in BtS (+2 happiness, +25% EPs and drafting a rifleman for 1 pop) and Slavery is probably the most powerful overall civic throughout the game (particularly with Kremlin whipping)
In general BtS civics are stronger than FfH2 ones, with
one very notable exception and that is Agrarianism. No civic in BtS would give +100% food production from farms. There is a reason for that. This is slightly moderated since the FfH2 granary is heavily nerfed compared with its BtS version which is probably the strongest building in the game.
I think you might be under the misapprehension, that +20% commerce is equivalent to +20% research and +20% gold. This is not the case. There are significant sources of beakers from buildings and specialists and the same for gold which includes shrines as major non commerce sources. So a +20% research + 20 gold would be much stronger than +20% commerce. In a typical late game economy commerce provides 75% of total beakers and gold. I estimate that a +20% commerce boost would increase the overall economy by about 15%. That is less than half the effect of switching to Free Speech in a fully developed CE in BtS.
Having said all that. If +20% commerce is too much for FfH2 (it is a different game afterall
) then make it 15% or 10%, there will a level that is balanced. The only reason I suggested a change from a gold bonus to a commerce bonus was not to make the proposed Mercantilism significantly more powerful but to make it more useful and attractive. There is clearly more utility in a civic that gives its bonus regardless of whether the player (or AI) wants to do research or accumulate gold, rather than restrict the options.
Not an interesting choice. It steps on the toes of Foreign Trade by improving trade routes. Besides, you were telling me Foreign trade routes are bad because the opponent benefits. You've convinced me.
I forgot, you're the person that doesn't understand trade routes. My mistake
You never heard of that thing they do in BtS? Fractional research? Differential...? Where to achieve a 70% science rate they run 3 turns of +100% gold and 7 turns of +100 beakers? A Consumption/Mercantilism combo would be pretty sick there.
Binary Research is what you're referring to. People don't use that anymore since the beakers and gold are accounted for to 2 decimal places. It was fixed in Warlords but was an important factor in Vanilla civ due to problems with rounding errors in calculations. Players sometimes hoard gold if they're mass building universities etc. but it is a minor feature of BtS now.
I suppose a Spiritual leader could use 10 turns of Consumption and Mercantilism (+40% gold) followed by 10 turns of Scholarship. But don't forget that BtS has markets, grocers and banks that give +100% gold all the time. The ways to manipulate the FfH2 economy are small beer compared to BtS, with weak civics and overpriced buildings. A 40% gold bonus from using 2 civics is not impressive.
If you improve Mercantilism to the point where it competes with Agrarian then it'll overshadow Conquest and the utterly pathetic Foreign Trade. Its not desirable that it be a default civic choice because what'll happen is a few civs will switch into it making trading conditions less favourable for everyone else so a few more will adopt Merc and etc etc
The good bits of Mercantilism are good but its up to you to decide if the bad bits are worse. For those who can't or won't trade its a good civic. There is its justification.
Well, as I've suggested elsewhere, I think the Agrarianism should be further weakened by making it :
+1 food - 1 hammer - 1 commerce
There would be less need to alter the balance of other civics then. Alternatively strengthen all of them:
Conquest (as now +10% mil production, low upkeep)
Mercantilism (as suggested above)
Foreign Trade (add a trade route bounus as well as the extra trade routes)