Stone walls would be a kind-of in between for Palisades and Brick Walls. The point in adding them would be so that players who join late in the world (when EVERY clay node is claimed or drained) will have the chance to build a wall that couldn't be bashed as easily as a palisade. The wall wouldn't be as strong as a brick wall but would be strong enough to help deter any attackers without use of a ram. To create the walls they would use stones, wood blocks, and mud (another suggestion.) You can create mud by mixing soil with a bucket of water.
Ideas for construction:
Cornerposts require 4 blocks of wood, 30 stones, and 10 mud.
Wall segments require 1 block of wood, 5 stones, 3 mud.
Gates require 8 blocks of wood, 10 boards, 30 stones, 20 mud.
Graphical ideas:
Cornerpost would be a tall stacked stone wall, with 4 palisade spikes (mostly for aesthetics)
Wall segments would be a stacked stone wall with one palisade spike (aesthetic)
The gate would be 2 cornerposts with a wooden gate in between similar to the existing roundpole gate but taller.
I'm no good at graphic designing or I would make an example, the wall would be very time consuming (due to the amount of different materials) so brick walls would still be preferred, but it would provide a safe alternative for anyone who does not have access to clay.
What do you guys think?
Leave suggestions and comments, any good suggestions I'll add into the main post.
EDIT:
I love this, that could even be the name (rammed-earth wall, house, etc) and could also include another set of buildings/structures.