Alright, thank you guys very much.
Yeah, I almost forgot about the raid mechanics part. (Probably because on Monk you can just roll around like no tomorrow)
I have seen raid fights from mythic Uldir, and I must say in some of them they were standing in melee range, where in a few others they were not. Maybe sometimes it's best to stay like "in the middle" between everyone so you get the least loss of healing on each player? Also, when you're standing right before the boss, how can Light of Dawn hit all players? Do you have to turn around all the time?
On a side note, 'perfect' healer numbers balance is something I don't really care about a lot, since I think most classes already bring enough utility to be worthwhile in groups despite maybe having a little less overall healing, and I certainly do not plan on hardcore progress raiding any time soon. Still, you'll never want to be a total fool in any group, even way before Mythic.
It's just that I really want to experience something different now, because they haven't changed the classes in such a long time now and it gets really boring to me having the same playstyle(s) for the third expansion now. I'm really afraid of the Holy Paladin gameplay consisting of 60% thinking about your positioning for hitboxes and mastery passives though, which is a big turn-off for me. I'd rather concentrate on my abilities and the fight that's going on around me.
I guess I might not find out just by reading about it or even watching videos. But I'll just wait a little while longer.