I haven't submitted any ideas to them. I just post here on the forum, which they of course read. If they want to take the ideas that is great.
I tried searching for my post about barriers but could not find it. If someone wants to link that it would be nice. Basically the idea is you spend silver to erect a wall where you want in your base. Enemy faction players have to attack the wall to destroy it. I don't remember what I specified, but I think it was something like 10 minutes for someone to take down one piece solo.