Also not really a big fan of adding a Normal typing to Chromera. spoo explained a lot of my worries pretty well, but I also feel like this idea zeroes in way too much on Boomburst and would end up turning Chromera into a Boomburst machine and not much else.
Zeroing into Boomburst is certainly a viable way to go though, as access to Boomburst is definitely one of Chromera's strengths. Without Boomburst, Chromera just wouldn't have any decent power once Color Change activates.
We tried to work with Color Change by making Chromera into a bulky booster. Bulky Booster Chromera needs a few turns needs to start boosting and has time to do so while the opponent struggles to hit Chromera effectively due to Color Change continually changing type effectiveness. In reality, we've seen it's not that hard to chain repeated super effective hits over those few turns that Chromera needs to boost. We could certainly try to continue the "bulky booster model that works with Color Change" by giving Chromera some new tools. However, currently I am not convinced that those tools will change the fact that the rest of the metagame is pretty good at punishing at Chromera's bulky booster gameplan. That is, giving Chromera new tools doesn't solve its biggest problem, which is that its bulky booster gameplan is really hard to pull off with Color Change not helping it and instead just hurting it.
Thus, since we tried to "work with Color Change" and saw that the results were less than ideal, I think it makes sense to explore the paths that "work against Color Change." And while "working against Color Change" might sound spooky, I'd like to claim that any buff that strays away from the bulky booster model is trying to "work against Color Change" because once you allow Chromera to make progress in battle in fewer turns, you're not really trying to use Color Change as a defensive tool anymore. You're trying to accomplish something in battle before the opponent has the change to chain super effective hits. So honestly....most (but not all) tools suggested in the thread so far are working "against Color Change," not just Boomburst as spoo's post suggest.
The idea of an exceptionally strong STAB Boomburst user that the opponent can "diffuse" by activating Color Change is fascinating to me. You have to have a some kind of gameplan to get Chromera in - you can't just switch it into attacks freely or else Chromera will lose its STAB Boomburst. So while Normal-type Chromera is a "Boomburst machine," it's more accurately "a Boomburst machine that switches into battle in high gear and switches to low gear once the opponent presses its exposed low gear button." Nothing else in the metagame really functions the same way, and it still uses Color Change in a way that's never been seen before in the game, so I think it's still a really cool way to make Color Change relevant to Chromera.
Plus, it doesn't really help with our Steel-type problem, which is one of Chromera's biggest overall problems.
Preliminary calcs of Choice Specs STAB Boomburst vs more offensive Steel-types are interesting to say the least, especially with boosting items. On the other hand, preliminary calcs against specially defensive Steel-types are much more tame, and having defensive Steel-types able to more reliably switch into STAB Boomburst is a good thing so that there's some defensive counterplay to STAB Boomburst Chromera. I think Boomburst not directly addressing the Steel-type problem is ok.
----
Finally, I want to highlight a little bit of Brambane's post because I think it's relevant to my argument and very well worded.
The takeaway from Chromera's history is that the Pokemon's design was a little too targeted for the metagame. The Poison-typing made sense to switch into Rillaboom and resist Grassy Glide and get a free switch off of coming into Toxic. The Dark-typing was a response to the prevalence of Knock Off Clefable and Future Sight. And Calm Mind could capitalize on all the slowish Special Attackers in the metagame and synergized with the natural bulk needed to answer Rillaboom. But when the metagame changed, Color Change's faults as a defensive tool became much more visible. Chromera was a bulky Pokemon, a Dark-type nonetheless, that couldn't answer Dragapult. It was horribly weak to pivoting moves, easily exploited by Toxic, and without consistent STAB reliant on Boomburst for immediate damage.
So, to answer the bolded questions at once, the issue Chromera has is it tries to leverage Color Change defensively, which is difficult if not outlandish. Chromera is simply too exploitable by pivots, Arghonaut, and Toxic to maintain a solid presence in the metagame as a slow, snowbally sweeper. The best direction moving forward is probably to abandon Chromera's original mindset of the Calm Mind deathball/"crit-me-not" sweeper. The best role to focus on for the Pokemon is what the Throat Spray Boomburst set tries to accomplish; a faster tempo, more offensive special attacker.
After reading Brambane's post and reviewing the sets that quziel posted in the OP, it's pretty indicative to me that Chromera is trying to lean into playstyle with a faster pace, but it lacks good tools to do so, given:
- Using Color Change defensively has shown itself not to work well in the current metagame, so its Calm Mind set struggles
- Chromera has crafted one of its more viable sets around the very niche item Throat Spray, making it obvious how Chromera really wants to have a faster-pace gameplan
- Chromera's Choice Scarf set (imo its most popular set) is mostly about just using Final Gambit to land as much damage as possible, which is probably as close to a fast-pace gameplan that it can get (but it faints in the process)