Part One of my fort is up. Goes from embark to discovery of the cavern.
https://www.youtube.com/watch?v=oGKeNnZ9wnM
Looks like a good start. Nice cavern find, that's sweet. You're probably going to want to wall up the lake edge though. Cave crocodiles are absolutely brutal to unarmored dwarves and they're a cavern 1 critter. As are giant olms.
Also, I now understand what you meant with the ice drilling. Neat trick, bringing the second layer down right under the first. I need to remember that. Also nice cavern sounding system. Hadn't known about that exploit.
A couple of tricks: Instead of ramping to the surface, dig upstairs on the lower level and then channel the upper level. Produces a hole with no ramp for ground creatures and no risk to the miner.
Undead do not need heads to reanimate. Currently some goblin's hand is running around and I think it's got 7 kills to its name. I need to go see the kill lists on those undead anyway.
Be really careful of those 'fighting the undead' thoughts. They ruined IvyLashes. The only good way to fight the undead is around a corner with a machine doing the work. Then apply magma.
Beware titans. They can step down one z level without a ramp and I believe they can destroy open bridges. I neglected to check if my titan was breaking them when I was running some trap tests. You may want to go back if you can trap a land creature via channels and floor it over. I know they can't break that.
Food won't rot in a stockpile, ever, afaik. Vermin will eat it though. You don't need those long corridors.