Heroes 6 - Discussion

Coins are a real problem. There's a limited amount of them, and it seems that even if you earn all the achievements, you still won't have enough money to buy everything.

I constantly get the achievement "Some kind of General" on every map, for winning five battles in a row without losses, plus I get some other achievements periodically, meaning they're not one-time rewards – that's how I accumulate money.
But I'm not spending it yet, just in case something new appears on the altar.
Although I spent about 10,000 of them – I bought heroes (not portraits) – like Tiangbo, Akamas, Zann, Hiroko, and some others – and they are quite expensive.