I've been practicing on an official Fast PvP server with x2 rates for everything and it has been a blast. I feel x2 rates is the best balance personally. x5 or x10 is too fast, x1 is a bit of a drag to get anything done.
Still know nothing really about late game, but can't wait for release day.
I've come a long way since these screenshots were taken. Currently in basic medium armour and about to get steel tools. It's actually really fun just exploring, I'm reading as few guides/using wiki only when desperate so I don't spoil this awesome experience. In particular it doesn't suffer from ARK syndrome; "Alpha T-Rex randomly runs out of the jungle and wrecks everything you spent 4 hours building, killing you 20+ times as you desperately run back to loot your corpse before it de-spawns."
I'd be up for clanning up and playing together on release day if anyone is interested?