Most of the 'cheats' listed I've never even heard of, and yes, I'd consider them to be cheats, as they circumvent intended gameplay.
The 'avenue on a cliff' thing - I know that one, having found it accidentally - would be considered more of a goof in the programming rather than a cheat... unless you're using it to access a section of plateau that normally couldn't be reached.
The Demeter one I've never heard of before, but it makes sense, as far as the game engine - Farms have certain requirements, and once those requirements are met, the Farm will stay in place (as long as it has a road and Maintenance coverage).
Building Walls to direct a Monster isn't really cheating, though you have to know what targets they're set for and what their strength is (Passive, etc.). Semi-cheating, maybe.
As I said, I'd consider all of them to be cheats, and I don't use cheats... aside from 'Mammaldrome' when I've got a Hippodrome running, because it doesn't affect gameplay; it's just a visual choice. The same with 'Cheese Puff' - it's just a visual choice and doesn't affect gameplay. 'Bowvine and Arrows' is just plain silly... seeing Orichalc-equipped towers shooting cows... one of the designers was obviously a Monty Python fan. But again, that one doesn't affect gameplay.
All of the other Ctrl-Alt-C cheats are indeed cheats, allowing you to get further along in an episode / adventure than you would by playing normally; it's like knowing your opponent's cards by using a mirror... not good.