this is 3*3 in pak192.comic, so going by that scale, each tile is 6*6 'knobs' in size. I think you could have enough variety at this size to make a pakset both look interesting and have enough visual clues to keep it playable, although it would be very, very abstract. Like, cars would be 2*1 'knobs', trucks maybe 3*1 'knobs' - track vehicles might be 2 'knobs' broad, but length 8 would be only 3 knobs in length. For variety, you could use half the scale for vehicles only (any smaller and you lose the advantage of "building blocks" for easy building, and charm, too)
While lego figures might be trademarked, the actual blocks are not. I guess with my example factory, the flags and fire could be problematic if lego really wanted to sue. But a visual style for a niche game is not the same as the use by a political party.