4th Edition and Chronicles Cube: the game back then

I’m aspiring to build a 360-card 4th Edition and Chronicles Cube (maybe make it expandable to 520 cards up to Alliances). I’ve already seen one really interesting Cube idea from one of the bastions of the community, and I may netdeck it.

What I’m striving to understand is the atmosphere of the game during that period.

(1) Famously, the 4th Edition Chronicles debacle is responsible for the Reserved List. How did the philosophy of core editions work at the time?

(1.1) Why were some cards not reprinted (Power 9, dual lands)?

(1.2) Was there rotation and standard format at the time? Was leaving these cards out of the collection a deliberate choice because they did not think they were fun cards? Or were people allowed to use previous core cards not reprinted in competitive play?

(2) The cube with 360 cards I've seen is only 4th Edition and Chronicles. Were the expansions (Ice Age block) designed to complement well that year’s core set?