Liked it pretty much.
Nice operation. I still wish this operation and the RN event will be joined by the British DD line. I'd wish for an adaptive difficulty in this operation. While playing with mostly t6s, it was quite challenging to get 5 stars. In the other hand, playing with mostly t7s, I felt it was rathar a matter of not sailing onto the minefields and 5 stars would be granted. The mayhem of land batteries, racing torpedo boats and air raids gave a nice historical perspective of the chaotic state that operation went through (thumbs up), but I felt that it was more challenging when less t7 were present. Difficulty could be raised according to how many DD with def AA there are (since the air raids become less and less effective) or on how many t7 DDs are present (slightly hp buff for planes and increasing one extra torpedo boat per attacking flotilla, perhaps?). But, please, don't limit the operation to just one tier. Having a mixed bag of different tiers is way more fun (any chance of other current operation benefiting from this policy and getting multiple tiers as well?).
New Arms Race Mode
Thumbs up. It will make the life of t8 much easier - yeah, I imagine everyone here had that accursed match were you were the only t8 among t10s and had only another t8, in the enemy team, to share your misery with. It will benefit those who like to play aggressively with their t9/t10; not the best game type for campers/snipers, though. Couldn't test it with CVs (in the To Do list for the next round) to see if it was possible to reap the buffs through other players.
A second point is that I believe this battle type should be eligible for some campaigns (screenshot points to the American campaign task 1, for which all battle types are eligible, except Arms Race). I support this battle type becoming eligible for the other two campaigns which are playable with only t8+ as well. But for task 1 and 2 of the American campaign, I would really miss it and wonder why all other battle types counts to the mission, while Arms Race doesn't.
Noticed, but don't think the changes in island layout will impact that much, except for the missing 4th cap (D cap) in North, that will be a major change (and, on a personal side, I'll miss the 4th cap).
Thunderstorm Front in Random Battles
Much better than now. I can't wait to have it implemented right away. I'd, however, ask for bit more of white covering the landscape as even the slightest drizzle cuts visibility to minimal levels, let alone a full storm. Furthermost islands should completely vanish behind a white curtain. Closer islands should have their profile recognizable, but most details washed out in a whitish blur. Besides the heavy clouds and lightnings that already marks the storm, the eye of the storm should appear as a white wall that conceals everything inside (except for a shooting ship, that flashes for 3 sec and then disappears; that mechanics is fine). Lightning flares illuminating ships is also a pretty nice feature.
Don't know if this is the place for further suggestions, but the current storm mechanics could just be renamed to "heavy fog". And instead of being implemented during the match, the match would start with the lowest visibility and gradually be incremented so that, around 10 min of game play, visibility would be back to normal levels.
Clan Base 2.0
I will miss the Hamburg City Hall (personal background) in the current clan base, but I'll still welcome the new clan base. Coal and steel facilities are very nice features. The reward on the live server should apply for those who just joined a clan and helped the clan develop all its facilities (and not only for those who formed a clan).
Interface and Other Changes
Nice to see commanders' skills and signals hints, so that you don't waste signals/skill points. I usually refer to wiki when I have a new ship in port, but that's still useful help. I think specially new players will benefit from this new feature. New flooding graphics is also a nice feature.
Nice. Works better then the current spotting mechanics.