Making marksmen less squishy is fine.

But only if lifesteal is made less broken on marksmen. With lifesteal strong in this game you either 1shot a adc or get draintanked. Without thornmail tanks and some juggernauts actually heal marksmen. If Sion wasnt strong i would ask for lifesteal too not work vs his passive.

Really the game could do with less damage rather than marksmen directly being less squishy.