Okay...first off, I had to put "Ultimate" in the title because the idea of articles titled "The Ultimate Checklist" amuse me since software changes so often.
I know I have Codex's theme checklist, but that covers Theme Development a bit more broadly than specifically closing in on the "have you styled this CSS yet?" aspect of it. Any idea if there is an itemized checklist out there which just cites just the STYLING aspects that you should edit/add for a given WordPress theme?
Some I have found that do this format but are outdated:
For me, my biggest flaw is that I always forget one aspect of styling and only notice it later when something doesnt aesthetically jive with my theme's color scheme. So having a STYLING checklist that I can combine with the broader Theme Development Checklist from this site would help.
Dont forget the milk!