healing certainly not the easiest on higher keys. You have to do everything DPS does AND heal.
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BfA was a differenet beast. I had 90% versa on regualar pulls. Damage was still big, but there werent so many 100% to 10% dips which SL brought us. With a good and prepared group it is ofc. easier to heal, but there still is way more stress than a ranged dps gets also healers do damage too. RDPS will always be easiest role to play in dungeons and hands down least amount of "stressful" experience. And let's not forget there are melee healers, those guys are masochists.
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maybe you tank does small pulls? There are spots where you need to kite in a +15 if you do appropriate pulls. Also depending on affixes, like raging, necro, bolster, sang is forcing you to kite regardless.