I think the Endwalker media tour BLM looked very promising and fun, iterating well on how it played in Shadowbringers. However, a couple changes between then and now feel rather last minute and undermine what I feel makes the job satisfying and engaging to play.
The first is the thundercloud duration. An increase in the duration of thunder and an increase in the duration of thundercloud is fine - welcome, even. Though I prefer the old system where thundercloud is a shorter duration than thunder, the new system is fine too. My issue with it is just how long it is. 40 seconds allows far too much leeway and feels rather unfun to play around with, even if it's demonstrably stronger. I'd much prefer it if thundercloud was brought closer in line to the duration of thunder, else I'm afraid one of the parts of BLM optimization that I enjoyed quite a bit will be gone.
The second is the change to paradox. In the media tour, the only requirement to be able to use paradox was to get 3 stacks of astral fire or umbral ice and swap to the opposite element. This meant that the Shadowbringers optimization of occasionally skipping blizzard IV when movement allowed for it would stick around - and even feel more like an intentional game mechanic rather than the admittedly janky implementation it had before. Standard rotation would still be ideal for when movement was required in the next AF cycle and for when you were unfamiliar with a fight, and B4 skips would remain a small damage boost for when you were able to execute them correctly. That makes for (in my opinion) a rather fun gameplay dynamic of looking for times when a B4 skip could be done and feeling rewarded by a slightly higher potency per second.
In the version that shipped to the endwalker release, however, paradox now requires the player to accumulate 3 umbral hearts in addition to 3 stacks of umbral ice in order to gain paradox for the next astral fire cycle. This effectively makes B4 skips nearly always worse than a standard line, and pushes them even further into feeling like unintended side behavior (something that, to my knowledge, yoshi-p said on stream was not the intention of endwalker BLM changes).
It feels like, regardless of the intention of these changes, they weren't fully thought out. I'd love to see paradox changed before the savage tier as I feel that's the biggest thing holding EW BLM back from being genuinely more fun than ShB BLM. These changes, on the surface, appear to have the goal of making the job more accessible. In practice, however, I feel that even if B4 skips are a thing the job is just as accessible as it would normally be. Removing them only limits creativity for higher-end players while making virtually no difference for the lower-end, and that feels like a step backwards.