“Freeform” typically refers to barricades that can be rotated the full 360 degrees on all three axes. Sometimes it’ll also refer to the barricade equivalents of structures, such as doorframes and garageframes. (So, basically, anything added in the Freeform Barricades update).
I’m not sure which way I’d take it, but I really don’t want to go from wood to metal and then be left with 15 wardrobes of wood walls.
Part of it kinda depends on whether or not certain materials are pure upgrades, such as “wood to brick to metal” in Unturned 3, too. Some people want Nelson to make the metal structures thinner, with bullet penetration through them quite easy. Imho that kinda unnecessarily nerfs bases, but 
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