I was just playing Mice&Mystics, there is a similar situation to Imperial Assault with the cat Brodie beeing too big for the game's scale. In that game, the cat shows up, but is just a paw token:

I'd love a campaign mission with AT-AT Foot Markers stomping around the battlefield, changing the line of sight... and of course beeing a threat.
Also, a small Tileset inside an AT-AT would be fun, too. Would be very small, but you could make both levels with an stair/elevator tile connecting upper and lower part ![]()