The earlier frame for Shieldlands was as a Greyhawk centered Domain-Building campaign for D&D 5e.

That's not what this Shieldlands campaign is about.

Well, what is it about?

• Where is home? Is it in the court of Earl Holmer in Admundfort home? Are we knights of Holmer's court? Or do we have our own home base on the mainland, near the Horned Society or Bandit Kingdoms border?
• Characters? Are we wide open, or restricted? I'd favor restrictions, but ain't married to it. I'd prefer No orcs, ogres, gnolls, goblinoids, or furries. Preference for Lawful, maybe Neutrals are ok. Basically no monsters. Half-orcs? Half-Ogres?

Serious Agree!

• What do we do? Mixture of Megadungeon, Quest and self motivated? Do we do base development like Worm's Ferry?

We should only have base development if the base may be attacked. So, let's attack our bases! Maybe the Shieldlands are a few months from being overrun?

• A note on Megadungeons: I think they are best if there is no real travel time to and from the dungeon and home base.

Acknowledged. Maybe on an island in the Nyr Dyv or North in the Plains?

That's way too far away. It's gotta be like 1-2 miles from home. Pick the homebase, there's your megadungeon; in Gatavia III, we had a ruined villa we fixed up right next to dungeon, once we were exiled from the good town. Pits of Damnation were right under our feet when we were at the Frat House.

So, I'll make a spooky old fort or something that has been gifted to the newly minted PCs that just happens to have an extensive old dwarven mine complex below it that has been claimed by all sorts of nasties.

The question of Canon

The World of Greyhawk with the Darlene map was published in 79 and 83 with explanations by Gary Gygax. The date of the Darlene map was “Common Year 576”. After that they advanced the timeline and went through the “Greyhawk Wars” with a lot of changes in the political landscape.

Much of the online info takes into account the advanced timeline and Greyhawk wars. While this makes background research simpler, it makes the Darlene map not entirely as useful.

I'd prefer to keep the campaign canon cut off at 576, which means just Darlene and Gygax. It makes some of the online info dodgy but I think it makes the map more useful, and that's the biggest appeal of adventuring in Greyhawk anyway.

In the advanced timeline, the Shieldlands have been conquered by Iuz, who also absorbed the Horned Society and I think the Bandit Kingdoms. I'd rather play with Shieldlands, Horned Society and Bandit Kingdoms intact.

Do you have opinions?

OMG. I do not. IMHO canon is between our players, not in any book or website.

I just brought it up because of some Traveller experiences where folk would try to count on online canon information about the Spinward Marches, when I was working strictly from the original supplement. It does become a problem from time to time.