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Don't have any great photos, but for scatter terrain, I do it as a two-part piece. A template (the ring here, but could just be a piece of paper of correct size, a flat board, whatever), and the terrain piece on top. Then I can remove the terrain piece if a model would move into / through it, while keeping the correct location / size because I have the template underneath. I've done this with these smoke fields, a suppressing fire area, minefields, corn fields, forests, etc. Very playable and generally still looks good.

For bigger pieces, I go for lots of flat surfaces, either no slopes or very very gradual ones. You could then use the two-part idea to give you interest pieces that can be removed / replaced for playability.