The worst is when a unit have can spawn another at a cost (like conquistadors) and you suddenly realize that this cost too was increasing, when you though it wasn't ...

I personally think, it's balanced: It makes us be careful of endangering/sacrificing expensive units. And some units' prices scale with their number on the map, which means they become cheaper again, if they die.

It's a strategy game, after all, not a rush-down-opponent-and-destroy simulator where only the stronger economy/production counts and nothing else.

Especially those who discover landmarks lose half their value after the whole map has been discovered... Spamming them early on defeats the purpose of a strategy game that is also meant to recreate RL exploration.

I don't know about normal speed, but in slow speed (i almost only play at that speed) i usually don't make more than a couple pionneers and it becomes costly quite fast. To the point of me not using them, the return on investment just don't feel worth the cost.
And there is little cap at the cost increase, except for the max XP we can stockpile, so it's actually not that balanced from my point of view. I absolutely understand that the cost change inbetween ages, and that some things may increase in cost while playing, but the scaling is too hard, and capping at max domain XP storage is actually too much as of right now.
I thing the max cost of a couple powers should decrease, that some powers that have a cooldown shouldn't (like immigration and tourism) and some things should not even scale at all. Plus forced march is fine most of the time, but in some ages it suddenly gets a lot more costly than necessary, which makes me stop using it.
And in the current version, the best strategy is still to have a superior economy (at least i've always been far superior to the AI by thoses means) .
Plus, scouts does not have to discover and explore landmarks as their only purpose. They are still very usefull to me once all of them are done.
So what i want here is not a removal of thoses costs, the way they scale, or of cooldowns. What i personnally would like is a way to make it feel fair and balanced.

I realize this is an old thread, but it'd be pretty straightforward to change the progression for those powers.

You could replace the power and give it a different:

Less intrusively, you could inject a card that applies:

(SUB, ADD, MULT, and SET are all supported operators, so you could just set the progression factor to 0.)

Just replace the original power with one without the progressive cost and unlock that one instead. Don't fix a graffity by painting another... remove the graffiti.