I hope you can find a way to put intelligence gathering regarding other movements inside the game too, like colonization plans or attack/defense plans while at war.
It will be quite easy to do this in a war too.
You won't be able to move ships freely to attack. You can however position them to defend your stars or put them in stars that have no colonies.
They will actively patrol their position. So when someone wants to attack you they will choose which ships they want, regardless of where they are and choose where you want to attack and how you want to attack. (too spread out ships will take more time to attack).
For example, you have 20 ships, you choose 10, pick your enemy homestar and then you can choose what you want to do there.
Attack and retreat, attack and bombard, attack and capture a ship, attack and invade, attack and blockade.
The game will tell you how many turns it will take for your fleet to get there.
Now you have a chance to discover they are attacking you, by having lot's of ships on your border and/or on the star they are attacking, by having active radars and also by spying on them.
If you do discover they are attacking you, then you can make a plan to reinforce that star, or maybe even intercept them before they reach there. Just like an attack plan you will be able to choose which ships you want to send and your plan.
To colonize a world you won't send a colony ship and there it is, you will actually select a planet, tell your intention of colonizing it and then it will slowly get colonized as people move there, you can however spend more money to get it faster.
Civilians will also colonize planets on their own, which you can later pay to upgrade a civilian colony to a military colony where you can control.
So spies can also discover your colonization plans.
So I Wondering if We going to Have Custom Race Choice that we make our own
Yes, definitely. This is the part that I love about 4x games.