The 4 hour window is great, but I think it would be even better if it was 4 hours and also influenced by other factors - for example widening the window with every citadel in system, and decreasing the window with friendly strategic level. That way it can be influenced by defenders and attackers alike and lower priority citadels would be easier to kill, but higher priority ones harder - rather than every citadel being the same 4 hour gamble.
I really don’t like the 490km lock range or the GTFO additions, the lock range makes an already powerful structure even more powerful and negates the only tactic we’ve seen used to attack an online Keepstar (Titans at edge of lock, with FAX just out of range, ready to engage defenders). The GTFO still hard tackles capitals for it’s duration which I don’t know if it will be the case for citadels, but I think it should be looked at if it is.
Edit: Assumed GTFO would have 100km range, but on SISI it’s at 300km. That’s monumentally dumb, and a huge buff to citadel defenses when half the community complaint was how hard they are to engage in addition to a hostile fleet.
The invulnerable-fitting timer is also kinda shitty, it means there is no effective difference between catching an onlining citadel and showing up to its final timer which was determined to the second by the defender. The defenders of an anchoring citadel already have the exact timer advantage and the knowledge which the attackers have to discover - they shouldn’t also have a fully operational structure on their side.
Not being able to force a weekend timer is still a huge issue. TZ tanking is kind of addressed but TZ tanking combined with weekday tanking is still a major problem that Upwell structures have.