For finishing the  game's most difficult content I think Lydia shall be looked at again by game designers.  I mean players invested tons of resources to pull/level-up champions and keep trying for months to finally beat all stages 3 star.  Its a heck of effort that merits adequate rewards better than just this epic-equivalent level of lego.

Her damage is below average at best, her kits has very limited impact.  Its safe to say she is on the bottom tier lego list.  

Her passive on 9 turn(booked to 7) cool down is a joke, right now players are facing 2-3 revivers in arena,  this long cool down skill can be completely ignored.  I suggest to put in 3 charges to this skill, that means it can block 3 revive attempts then it goes on cool down.

Her skills all have some sort of debuffs, but nowaday in arena we are facing teams with high resis also lots of debuff block skillers.  These skills she has are really only somehow good situational.  Please consider have her to strip debuff on A1 then apply  fear if debuff removed.  Her A3 shall be like warlord's which simply put skills on cool down instead of trying to apply debuff. 

Taking her out of shard pool is the right decision, but since she is so difficult to obtain and unique please do some rework on her.