atlas/events/bosses were a great way to get some equip and currency as a newer player and at least try to bridge the gigantic gap that older players have. sadly after the changes this is no longer possible. (this includes worldbosses, where some like sismond/Kolanda/zalkyris have longer not been killed by the community)
i do get that you want to evolve the game, but in the process took one of the few ways for newer players to catch up (not everyone has maxed out gear). it is already insanely hard to get anywhere near doing some dmg on the endgame things like wb/atlas mobs if you are starting out from zero (without putting tons of IRL money into the game). the game still is very grindy if you are new, these activities were a nice change and gave a good return on your time investmend. anyway, thx for working on the game and all your time and effort. keep the new players and smaller guilds in mind if you do things 
Hello
New players was quite a important reason this change was introduced. Previously Boss Event/Atlas Defense was being done by high end players in very small groups (often even solo, quite often duo). Leaving smaller players struggling to make progress due to being weaker and not invited often unless inside a guild who took people along. Now players have the chance to contribute by making the event weaker for stronger players, a much more meaningful contribution than just standing there pulling the lever, as well as having easier time if trying to go further with weaker parties.
Also alongside this, the randomness of boss event was removed, previously bosses were having random effects which reduced dmg by over 50%, more offensive dmg by 50%, or simply having larger amounts of HP. Now this difficulty is mostly static, allowing new players to not be penalised by randomness, and still having easier time, and bosses are substantially weaker without HP buffs.
About Atlas Defense, it may need some finer tuning for substantially weaker parties based on feedback from some weaker players who have tried this so far, and it will be implemented before next weekend, however from looking at data from higher end groups, so far the results behind this change seem as expected in regards to run times (10-20 mins).
To the other posts(Too many to quote):
The original data of 40-45min runs was due to 1 change which was missed when updating server with recent patch and was updated on Saturday around 16:00 (Removing insanely high crit resistance), however some groups had already attempted it prior to this. This change alone allows a larger class diversity, as well as making the event significantly faster, which is clear from looking at event times made since the patch, so if you were in this group and wrote off the event as being not worth your time after the change, it would be worth retrying it before dismissing it fully.
Greetings
