Even with +50% health, I find myself melting through the enemies and bosses as I progress through the run, even with basic attack — to say nothing of the player scaling that comes inherently from medallions, their upgrades, and medallion slot unlocks. Meanwhile, almost all my deaths and the majority of my hits are early on (though it's moreso due to the enemy density rather than the enemy health).
This has been an issue for a little while, but I think enemies could use a health boost in later levels, and a slight decrease in early ones.