Overall, I'd have to say I dislike the changes. While many of the biggest issues with Nexus Blitz were fixed, some of the things that made it the most fun were also changed.
1. You know the first event in champion select - this is great because it doesn't come as a surprise and you can be prepared for it.
2. Most of the events start in the middle of the map - no more automatically losing an event that's near the enemy's inner tower when you haven't even killed the outer yet.
3. Graphics - the map is clearly a lot nicer looking!
4. The MAP - holy hell Riot what did you do????? Why are there all these walls in between the two lanes all of a sudden? We LOVED how the old map was so compressed and chaotic. You don't need to start moving this map closer to summoner's rift again. The big walls between the two lanes make it way too hard to swap back and forth between the lanes as a laner. The biggest draw to this game mode was that you could influence EVERYTHING so quickly. If I played top lane, I could go help my junglers so quickly, I could go gank the bot lane so quickly. I never felt like I lost a game due to bad teammates because I could influence every enemy on the map with my presence. Now the two lanes feel so isolated - if I'm in one lane and the other lane gets ganked or takes a bad trade, they're going to die before I can get there to help.
5. The "Series of Duels" event - I'm not sure how champions are selected for the 2v2, 2v2, and 1v1 skirmishes, but regardless this event feels BAD. I was up first in a 2v2 as Ahri, allied Kayn, against Leona and Kassadin. Kayn walked straight towards them, got Leona E'd, then died 100-0 without dealing any damage to Leona and Kassadin. I was 1v2 against two enemies with 100% health each - with no towers to protect me in the arena. I 1v2'd, killing them both. That felt GREAT. What sucked was my team then proceeding to hard-lose the other two duels and we lost the event as a whole. As per the above point - Nexus Blitz gave us influence. If I can hard-carry a 2v2 duel and still lose the event that just feels terrible! Also imagine being in the 1v1 and not even getting a chance to do it because the first two duels lost? (If anyone cares, I hard-carried that game as a whole still). I'd recommend having all the duel winners get to come back for a final "winner-take-all" duel. So if your team wins all 3 of the initial duels you win by default. In the example above, Kayn and I would have returned as winners in a 2v3 duel (where Kassadin and Leona would have sat out). If the 1v1 duelist is the only winner he goes into a 1v4. Give us a chance to carry the event.
6. The "Kill all your enemies" event - The "rules" to this event were never clear. The pre-game text told you to kill all your enemies. It never mentioned you'd get ridiculous CDR and multiple lives. After I died and noticed I was in a Zhonya's-esque state I moved over and started watching my team fight. I probably stood there for 20 seconds, alive and ready to go back in, before realizing I actually wasn't in stasis anymore. There also didn't seem to be any indicator of how many lives anyone had left. We eventually got to the point where it was me and Zed versus the enemy Jinx (different game from above) and she had just died and was respawning under her tower. We figured it made sense to dive her as she came out of stasis, given it was 2v1. We dove her, killed her, Zed was already low so she killed him before dying, and took me pretty low afterwards. I died to the tower. We lost, because she had another life left. That felt pretty crappy, how were we supposed to know she had another life still? Especially I assumed I must have had the most since I sat off to the side for 20-30sec after my first death without realizing it (who knows, maybe she did the same). ALSO, my ult was on a huge cooldown afterwards, even though it was active before the event. So it seemed that I got this huge CDR during the event, but since I didn't use all 3 charges before dying I took the full cooldown after the event? (Maybe that's just a bug). My recommendation would be at a minimum to flash the screen and send a big notification when you "respawn", or show a countdown timer as respawn time. Also have some sort of indicator of your number of remaining lives over your head when in stasis waiting to respawn.
Not changed and is still an issue
1. The rift herald is still way too strong. This was my biggest issue with the first map, and it remains a problem. Rift herald gives you baron buff PLUS rift herald pushing with you PLUS seems to give you like 100 extra minions. Literally in our game-winning push I was getting super-creep blocked by my own minions that I had to use my ult just to move. My enemies were so creep blocked too that I was hitting charm for free. The entire map was covered with buffed minions everywhere. Rift herald was the true reason we won that game. I carried to keep us in it (and I made the herald call), but at the end of the day there's no way I carry that game without us getting that herald, then proceeding to summon it and take every tower through to their nexus on that single push (we had no towers prior to that, and Nasus plus me [I was fed so doing 400 damage per auto myself] just kept killing the towers before Rift got there]).
The events need more clarity - I need to be able to know what's going on and be able to tell the current status at a quick glance. I won't have time to read a full tooltip (assuming there was one) when we're in a confined space for a 5v5 deathmatch with unlimited cooldowns...
and the map was better when it was more "open" and you could help your teammates more easily.