She was great in arena pre-Traya. EP lead was meta and her AOE daze shut that down. I ran JTR BB8 R2 RT Holdo for a long time and did very well. EP was cake, Bastila was cake, anything other than Traya was cake. Even with Traya in arena, I still did great because most people ran her under EP until Bastila showed up. At that point people switched to Traya lead and I struggled, although I was able to do ok against her depending on RNG.
The meta has moved on but she's still very good in TB/TW.