Are you willing to play any spec from either class?
Shaman offers more options on play style. Rogue is always going to be strictly melee.
Enhancement Shaman is one of those specs that is just filled with WoW specific flavor.
Rogue is pretty generic among other MMOs and fantasy games. I see it as a unique experience that you would have a harder time getting elsewhere.
Enh Shaman has been bad in BFA, no one really denies it.
But Shadowlands is looking really good for Ele and Enh Shaman. It’s a genuine battle mage.
You’re not just melee, you actually make use of lighting bolt & chain lighting for damage.
Rogues will always have better tmog though.
Mail is… 
80% of the time.#
Although I am digging my current tmog and the HoV mail set a lot.