sterile oracle
In my opinion, the stellar novas Kiwami and Ars Laevathin as they are right now feel outclassed by the Theofania Inanis, Garden of Avalon and Edin Genesis Quasar.
The main reason for this is that the 3 stellar novas that outclass the two are simply better at doing what they do.
In the case of Kiwami:
Garden of Avalon provides much better support and defense whilst everything else does much better damage. Furthermore, Garden is much less situational and far more versatile due to its invincibility. Kiwami has very low damage in all modes and does not provide any form of healing. The only advantage Kiwami has on any of the other stellar novas is it's low energy cost syngergizing with it's free hit. With Eridani Kiwami has exactly 5 energy wit hthe right prisms and can be spammed as a panic button due to it giving a free dodge. But despite this, Garden can still be argued for due to it having incredibly high healing on crit and longer i-frames which can be situationally more useful
In the case of Ars Laevathin:
The main benefit of Ars Laevathin is it's high AoE and pierce, alongside a damage buff. However, Theofania Inanis, especially in Eridani's case, outclasses Ars in most aspects. Theofania has lower energy cost, more versatility (Moving projectile as well as large hitbox, two chances to hit, debuffing mobs), infinite pierce and, most importantly, energy recharge. This causes Ars to be worse for worm bosses and mob groups with high density. Whilst Theofania is better in Eridani's case without a doubt, Asphodene has similar no damage buff and it may be argued that Asphodene's theofania is worse than her ars in some situations due to it having bigger aoe. Despite htis however, the energy recharge of theofania makes it significantly better for destroyer and any form of high density mob group (Specifically Plantera's 2nd phase tentacles). This also gives it more use in cross-modding
tl;dr
Kiwami is too weak and outclassed by Garden
Ars is outclassed by Theofania
forest ivy
ornate flax
quasi citrus