I humbly request you to add a 5th tier of solar panels and accumulators, and that you make them orange.

Because then, we could fully color-coordinate tiers with rarity.
Common - T1
Uncommon - T2, both green
Rare - T3, both blue
Epic - T4, both purple
Legendary - the T5 i am asking for, both orange

That's a neat coincidence considering the colors are like that for a few years now.
I might consider adding another tier. But it might be too OP even for my taste. Each their own I guess and that's why you can disable tiers.
I might consider only enabling this tier if you have the quality mod enabled. But legendary T5 panels might be way too OP :D

Any name suggestions what might come after ultimate?

Im not sure about that "too OP" thing, legendary T5 (or any T5s really) will be expensive
For the name... I thought about something like "perfect" "(grand?) master" or "mythical", but i think i have a better solution:
If you lock T5 behind Cryogenic Science, you could go with a "supercooled theme". Like, IRL all our superconductors only work at really low temperatures, so it could be called like "Supercooled Solar Panels/Accumulators", and let them only be crafted on Aquilo.
I also considered "Promethium Panels", but then i realized that using promethium in anything other than it's science is kinda not worth it and upcycling promethium for legendary panels also sounds like a big nope.

Edit: Wait that theme only works if Space Age is enabled. Uh. Maybe something more generic after all?

Hi, just wanted to ask if you are gonna do this or not. I also have some additional name suggestions:
1: Flat out call it T5 Panel
2: Name it something silly, like "Cookie Solar Panel"
3: Name it after someone, maybe yourself. "LsHallo's Solar Panel/Accumulator"
4: Can you change the name the player sees without changing the internal name? If you can change the visible name without messing up saves, you could move "Ultimate" to T5 and add another name somewhere on T2 - T4.