I have recently painted my collection of Heretic Astartes which contains both very old models -- like the Space Crusade dreadnoughts -- and some very recent ones. I feel their design went the whole circle and returned to its roots. Excellent!
Important for breaking open landscape giving non-mounted troops some hope. Bear in mind that Roman legions were able to set up walls overnight and defeated the Gauls "with a pick not with a sword" »
To make small, round shapes out of cardboard use an office hole punch (available also with funny hole shapes nowadays) or better still a DIY punching tool used to make holes in leather belts and the like »