Hello Achilleslastand,
welcome to our forum and thank you for the question. I would ideally leave this to other players but in case, that you want answers directly from developer, here they are.

Achilleslastand původně napsal:

How deep is a learning curve, simpler on the Civilization side or deeper like a paradox title?

I would say that it is definitely closer to Civilization. The game has two tutorials, which allow you to play the game from the beginning (tutorials are inserted directly to your own game without forcing player to play "tutorial map" first). There are also tooltips and hints for literally every UI button and control.
There is number of optional features, which are by default turned off when you choose one of the lower difficulty levels (normal and higher difficulties have all the features turned on by default).
I would definitely recommend to NOT start playing the game on normal or higher difficulty. Start easy and I mean EASY:)

Achilleslastand původně napsal:

How many factions/sub-factions are there in the game?

For the campaign map, there is 20 factions, all playable and you can win with any of those (proven by testing). If you play custom maps, it is up to configuration of the world how many players will be on the map.

Achilleslastand původně napsal:

Does the game have a good variety of units as well as nation specific units, land as well as naval?

There is 5 "army types", every army type has 3 melee units and 3 cavalry units. There is also number of "shared" unit types (settlers, nomads, wagons, buildings, etc). There are there naval units (shared for all the factions).

Pavel-Ku původně napsal:

Hello Achilleslastand,
welcome to our forum and thank you for the question. I would ideally leave this to other players but in case, that you want answers directly from developer, here they are.

Achilleslastand původně napsal:

How deep is a learning curve, simpler on the Civilization side or deeper like a paradox title?

I would say that it is definitely closer to Civilization. The game has two tutorials, which allow you to play the game from the beginning (tutorials are inserted directly to your own game without forcing player to play "tutorial map" first). There are also tooltips and hints for literally every UI button and control.
There is number of optional features, which are by default turned off when you choose one of the lower difficulty levels (normal and higher difficulties have all the features turned on by default).
I would definitely recommend to NOT start playing the game on normal or higher difficulty. Start easy and I mean EASY:)

Achilleslastand původně napsal:

How many factions/sub-factions are there in the game?

For the campaign map, there is 20 factions, all playable and you can win with any of those (proven by testing). If you play custom maps, it is up to configuration of the world how many players will be on the map.

Achilleslastand původně napsal:

Does the game have a good variety of units as well as nation specific units, land as well as naval?

There is 5 "army types", every army type has 3 melee units and 3 cavalry units. There is also number of "shared" unit types (settlers, nomads, wagons, buildings, etc). There are there naval units (shared for all the factions).

Wow, thank you for the detailed and prompt reply.

Theres another game in making, Imperiums Greek wars, thats even better, same great devs as this titile.
https://store.steampowered.com/app/1183470/Imperiums_Greek_Wars/

athelasloraiel původně napsal:

Theres another game in making, Imperiums Greek wars, thats even better, same great devs as this titile.
https://store.steampowered.com/app/1183470/Imperiums_Greek_Wars/

Yep, got it wishlisted. Looks interesting.