Are we really having a discussion about 3 day early access being better than an expansion release day. (That had over 10 million players).

Though if you want to compare:
WoD launch: 3am lag fest, crash meh I'll go to bed. 8am 0 problems for me after that first night.

Heavensward:
Friday night: can't create new character.
Saturday night: can't create new character.
Sunday morning: can't crest new character, (refresh for 3 hours). New character created.

I'd probably wait until Tue if you really want to brag.