Giving Guerrilla II for free would be a bit problematic, because it would be granted to all melee units (as well as all gunpowder and archery units). G1 is blocked for melee units - but G2 is not (which is why Gallic Warriors are able to choose to get G2 when they level-up). This would mean that all melee units would have G2, and thus they could pick G3 as their first normal promotion. That would be some rock'n powerful macemen coming out of every dun city. That's probably alright for flavour, but maybe too powerful in terms of balance; and it would completely undercut the uniqueness of Gallic Warriors.
gah! I wasn't exaggerating. The AI could have literally 5 times the number of military units as you, and you could still take a coastal city very easily because currently there is no way to defend against a sneak coastal attack. It's unlike a land invasion, it's unlike an air assault. A water based attack is completely different. Add to that the fact that in Civ, losing 1 key city will decide the game - either a legendary city or a capital. Does it effect every game? No, but this scenario plays out in most of my games that make it to the late-game.
As for the Dun, 2 xp would work but lack flavour. However, giving guerilla promotions to archery units is near useless for the celts. If the Dun provided a more useful promotion, say, shock, it would work better.
Well, let me put it this way: If I was in an adversarial multiplayer game against you, and I had 5x as many military units, and my job was to defend a couple of coastal cities for, say, 30 turns to win the game. I reckon I could do it without much trouble. And if our roles were reversed, I'm pretty sure you could do it too.
I agree that coastal cities are extremely vulnerable compared to inland cities; but 5x military is a very large advantage. 5x military would mean for every enemy fighter trying to air-strike me, I'd have 5 of my own fighters ready to intercept. For every battleship, I'd have 5. For every marine, I'd have 5... (although I probably wouldn't be building marines for defense.) The main problem with coastal cities is that the enemy can attack them from a long way away, and so they can threaten multiple cities at once. But with 5x the number of military units it wouldn't really matter that multiple cities are threatened, because the important cities could each have
more units in them than the entirety of the enemy's military. Beating those cities would be near impossible. (unless you were using nukes, in which case all bets are off.)
As for the Dun, 2 xp would work but lack flavour. However, giving guerilla promotions to archery units is near useless for the celts. If the Dun provided a more useful promotion, say, shock, it would work better.
The 2xp would be only for melee units.. so there is a little bit of flavour still. There's nothing currently in the game which gives xp only to melee units; so that would be a unique effect. (The Native Americans' UB gives xp archery units, and the Spanish UB gives xp to siege units... so it's not
completely unique.)
Shock would be a more useful promotion than Guerrilla I, but I don't see it as being particularly flavorful. Also, shock would be granted to a larger subset of units than the current free promotion is. Shock is available to melee, archery, mounted, and siege.
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That said, I think "intercept" missions in your own culture borders, for battleships and/or cruisers and/or subs, would be realistic.
How do you envisage the game mechanics for that? Perhaps extend sea-patrol so that adjacent bombard missions count as attacks (in addition to adjacent pillage missions)? Is that what you have in mind?
, but don't add the experience.
