@NationGamer090 I think this has been discussed, it would be a nice addition, but I think there might be problems with pathfinding. Palisades and walls already work like a painting tool (just keep shift pressed), so that shouldn't be much of a problem, I guess.
Regarding palisades, I never use them, are they used in MP? I think they should be the preferred defence building early on, but seem underpowered to me. I think they should be faster to build: for Spartans, a house costs 150 wood and is built in 50 seconds, while a palisade costing the same amount of wood is built in over 2:30 minutes. This seems unrealistic, given that houses are more complicated to build, but none of that is really a problem, the problem comes if they are, on top of that, not even used because they are mostly useless. Or maybe people don't want to increase defensiveness in the game.
My idea is to integrate this directly into the game, so that after 10 minutes of reading, anyone can understand what to do and how to succeed.
This will lower the entry barrier for new users and immediately reveal the game's full beauty and diversity. I think this is something that's sorely lacking!
And I truly believe this will help 0 A.D. grow its community.