Having hunters with the ranged and aspect of the pack on is actually by far the best way to reduce mark ticks and shadow crash hits.
Pack can reach the ranged group even if the hunter(s) are in "melee".
I can't speak for other groups, but we have cleaner kills when we minimise the people at range, and spread them out as much as possible (ie no more than 3 people to a single cloud). I'm assuming this is due to a combination of oceanic lag and poor playing, but it works.
With the new mechanics, we found the best way to handle Vezax hardmode was as follows:
8 ranged dps, divided into 2 groups of 4. One group stands on the far left of Vezax, the other on the right. Each group has 2 people standing on each edge of the shadowcrash to maximize dps, and minimize movement and healing done to Vezax.
We ramped up to 7 healers, all in melee range until the Phase 2 transition, when 2 disc priests run out to the ranged groups (1 per each group) and we kept a holy priest in melee range. 2 paladins fulltime healing our MT who tanked both, a resto shaman also MT healing with a few chain heals on the melee, and a resto druid MT healing with a few WG's on the melee. The holy priest assisted healing both ranged groups.
We used a paladin tank, and external cooldowns for every other Surge. After the Animus dies, we do a few soulstone+suicides for a couple healers to get back some mana, and all the OOM people at range just spread out and focus on staying alive while the melee finish off Vezax.
We just run with 8-10 ranged usually. Half on left, half on right. Eventually the shadow crash gets wider so half the ranged don't even have to move for crash or mark. Add a disc priest on top shielding the ranged from within crash and there's little healing done. Last kill was around 2.6 million healing, and that was with 1 guy messing up and dying to mark when he ate a crash.
Would be even better if we had a hunter but apparently all hunters suck at this game.