If your opponent is similar rating what does it matter how 'hard' the map is?
If the map is hard, you are playing the map more than the game. That is not fun for most players who are low.
Maybe you could have a sub 500 rating for new players but really you think a 1000 player can't do seton's?
Yes, they can't play the map.
If you only play ladder most likely you will never play seton's. The most iconic map there is.
Oh no. If you play ladder you will also never play DualGap or Astro and they are iconic maps too lol. Just play global if you want to play them. Seton's is not really a 1vs1 map anyway.
How are you going to learn to play these 'hard' maps if you don't practice?
Get better at easier maps first. No real point in playing hard maps when you can't even do easy ones.