Hey! I’ve actually done quite some BGs on blackrock and I can try shine some light on the situation.
I do understand why some people find the current situation problematic.
So let’s try break it down.
The main issue is the faction imbalance in wotlk pvp with alliance have the dominated population.
When we introduced crossrealm we quickly ran into an issue with long queue times for alliance.
Blackrock, being the only server that really don’t care about what faction they are became a huge part in balancing out the queues by allowing them to become horde.
That had a huge positive impact but created an illusion of unfairness with getting “low geared players”
We’ve been monitoring the win ratio and funny enough it did not matter if blackrock became horde or not... the win ratio was still 33%.
The queues took about 20 min for an alliance players to pop. Not acceptable.
With like over 200 alliance waiting for horde players to queue.
So with that data we can draw conclusions is that the mercenary mode does give bigger benefits than it being disabled.
You mentioned full crossfaction for all realms. Yes that would be the best solution but sadly both icecrown and lordaeron is strongly against appearing and playing as the opposite faction.
What I did do to improve my win ratio was to queue as a group of 5 with players I could trust doing a good job.
Our win ratio got bumped up to 75% simply by running a premade with full S7 gear.
I hope this helped you to understand the situation better and sadly I don’t think there’s any good solution until people change their mind regarding playing as the opposite faction.