Battles in the game look quite interesting. I think they should get a separate game mode. This can diversify the game experience and/or provide an alternative game mode for those who want to command in battle, but do not want or can not currently play the main game mode. This mode can also be used to learn the combat system or improve the player's skills outside of the main game mode.

Types of battles are suggested when this mode is selected:

• Prepared battles

• Historic battle

• Custom template

Battle templates that the player saved when customize the battle (see below). 

You can also add a function for publishing your own templates and downloading templates from other users.

• Customizable battles

• Battle mode

The following battle modes are available:

• Skirmish mod

• Military campaign mode

• Siege mode

• Standoff mode

• Map

• Conflicting party

• Color
• Era
• Culture (including cultures of previous eras)
• Role (attacking or defending) - only for Skirmish and Siege mod
• Armies (number of armies and their composition)

P.S. Sorry for my English. Excuse me if I applied incorrect or inaccurate terms.

This sounds like a very good idea, especially from the angle of practising. The combat system is clearly on the more complicated end so a way to practice without having to commit to a full playthrough would be very good. Or even if not to practice, to try and test out some army combinations or some EUs you haven't used before. And of course just the fun.