I’m liking the idea of making towns more than just unit-producing places to defend. If we would have the option to have a city increase its fortifications and train troops to become more expertly, this would make them more significant compared to the towns. While a city’s fort bonus and greater population already gives it a higher priority to defend, they do feel like just another town in peaceful areas.
How about this: If you can look ahead a day or two and see that the city will soon be on the frontlines, you can choose to build better defenses instead of training more men. It will take longer (Say 12h) and it’s not cheap, but it will be for the best if that city becomes a chokepoint for your troops to intercept the undead. And it would make the troll’s pikeman card a fast way to buff up defenses rather than the only way.
And the ability to train your men to higher exp in cities is a good one as well. I suggest; it’s cheaper than training new troops but not nearly as efficient. And the more men in the troop, the more expensive. F.e.: Humans exp +1str gets a 500str troop to 550str, this costs 50 gold. This means it’s 1 gold per 1 str. The humans cost 250 gold for those initial 500str, so 0.5 gold per str if you were to train new humans, twice as cost-efficient. However, the training takes 3h and if you were to have a small troop of just 5 humans the training will be cheaper (5x1=5gold) as well. Typing that out, it might be smart to put a minimum cost in place, like soldiers<25, still 25 gold.
This way, already experienced but decimated soldiers can be trained cheaper (though the costs will rise exponentially per xp level) and players can buff up the troops against a force that will arrive in <6 hours. You can also spend that little amount of money you have left after buying new troops. And for all of this to be worth it, you’ll have to merge your experienced troops with new ones before fighting, after which the training will become rediculously expensive because the troops now number into the hundreds and you can’t unmerge them.
I disagree with the magical cards thing. There is already a bit of an entering barrier for new players, having to get a respectable collection of cards in order to play on par with the big boys, more cards would make this issue more prominent. Right now it’s not yet too bad. The equipment however would be more interesting. If this wouldn’t be a collectible card issue, it would make the gap smaller and it could even out the race differences a bit. F.e. Dwarves don’t really use a lot of mana, so giving them mana-improvements upon their weapons, like enchanting their axes.
And a small suggestion of my own; how about making certain units like the cavalery trainable in cities? Right now they are only summonable in card-form, if they could be trained in cities (higher costs and training time to compensate) it would be interesting as well.