I have completed the content for Vesta, and wanted to give some feedback and suggestions.
Overall: I love the concept of extracting resources from a gas giant. I also found far more enjoyment than I expected with the chance to play with fluids (gasses) in a bit more depth.
I started with the default configuration, "Normal Mode". I built a quick "proof of concept" chain of buildings for the science pack to be certain I understood the mechanics of the planet and was greatly surprised to find that I had already almost completed the planet, except for importing holmium ore. My impression was that Vesta content was overly simple and very poorly thought out. I was going to abandon the planet, but decided to give "Complex Mode" a try instead.
Complex Mode, in contrast, was a delight and the experience was exactly what I hope for in a new planet. I was challenged to explore moving gasses around in greater depth and putting together the production chain was highly satisfying. I appreciated the consistency between different gasses, algae, and various intermediate / end products. It is a little bit surprising that Normal Mode feels far less refined and consistent, even though it apparently was added later (if I understand correctly). In some ways, the experience reminded me a bit of Space Exploration (in good ways!), but in a more constrained scope. I am a bit confused as to the future of Vesta.
Having experienced both "Normal Mode" and "Complex Mode", I am a bit confused after reading through the mod description again. Which is intended to be the future of the mod? Complex Mode feels like the way the planet should be played, but Normal mode is the default and was created more recently in the overhaul (if I understand patch notes correctly).
A few notes on my experience, and what I would suggest changing to streamline Complex Mode a little bit:
Sand and Cerramic both seem an excessive as they are irrelevant to the planet's mechanics. They could be eliminated with no loss.
The large number of single-use intermediates in Complex Mode doesn't quite fit the typical factorio theme. I think this is a good thing! I like the focus on a long production chain instead of the normal factorio wide production chain. This adds variety that keeps the game interesting. That said, it felt a like Exotic Algae Clumps could perhaps factor into more recipes.
The unique buildings are a lot of fun, are all well designed, and greatly enhanced the experience, even though they seem a bit limited in what they can do.
The Infinite tech "Intermediate Productivity" seems an odd addition. It doesn't fit the theme and it solves a problem that in my experience so far, does not exist.
Notes on Normal Mode: My primary complaints were around obtaining Electrolyte (importing Holmium ore doesn't fit the theme) and Lithium (Far too easy for its use). Also, the rewards were incredibly powerful for almost no effort obtaining them.
Thank you for creating Vesta, it was an enjoyable planet!