ANY BG (not just epics) should feature multiple ways to win.
The most basic formula for this is:
“Strategy A” if you win the teamfights.
“Strategy B” if you can’t win the teamfights.
This formula allows teams to win both by outgearing, as well as outstrategizing the enemy team.
To give a basic example: Silvershard Mines has a “take lava and have a couple people get offcarts” meta, but there is an entire extra set of tracks to be used by teams seeking to outplay the enemy team. This is good.
Having multiple ways to win raises the skill cap, or the “ceiling” of what is the most skilled way one can play a BG. This allows for more opportunities to outplay, and shake up the meta to prevent BGs from becoming stale, boring, or “determined by who has the better comp/gear.”
That’s GOOD.
The “braindead” way to win should NOT be the most optimal way to win, but it should be available so that even those who are new to WoW, or new to PVP, can hop in and have fun! BGs shouldn’t be too complicated to the point where the average player doesn’t know what on earth is happening.
But having “advanced” strategies that are difficult to perform but objectively “better” if done right is a great thing for BGs to have, since it raises the skill cap and allows for experienced/veteran players, or premades, the room needed to make amazing plays and win the game in new or interesting ways.
If I were to make a BG, I would have multiple ways to win, multiple viable strategies, with an “easy, but sub-optimal” strategy being “obvious” to “get people into it.” Not having an “easy” strat was what I think led to Ashran being not as positively received as it should’ve been.
But look, as a premade leader, obviously I’d be biased in asking for “more” complicating mechanics and paths, as opposed to less, as it gives me, as an organizer, an advantage over others.