Shen's Last Gift has pretty fun mechanics. Wave based battles and an elevator mechanic that has you having to balance who to send up to the next level and who to defend.
I played through it as soon as it appeared in a New Game,

It is a brutally difficult if you do it too early, but far from impossible. If you are in to that type of challenge I do recommend it. They give you Shen and SPARK who will be carrying you throughout the mission.
Shen's got some great skills that can get you out of pinch when the enemy waves start pushing you back.
Spark's Overdrive can be clutch letting you get multiple shots in in one turn.
If you do take this mission super early, make sure you have specialists on the team, hacking is super powerful as all the enemies are machines.