I'm going to preface this with I wasn't playing league when the last iteration of nexus blitz was live.
- Super minions don't give as much gold as cannon minions, nor do you get global gold from them. Super minions give 90 gold, while cannons give 100 gold/30 global gold.
- Some rewards for winning events seem way more impactful than others. The sled, cannon, mega drake buffs, and poro king seem to help your team a lot more than a very short duration GA buff, statikk shock, and imho the worst one, the shield.
- Stat-stick is awesome.
- Announcing first event of the game in champion select is nice and helps influence what champion you pick.
- The 30 second timer before events start is good and lets you prepare for events, either getting in a last second buy to give you the edge, or letting you know you should go power farm to hit 6 before the first event. One thing I'd like to see is having the next event timer be pingable.
- I'm not sure how pairs/solo are chosen for the Arena, but there are definitely times that it feels like a very one sided matchup. Also if you didn't plan ahead and used your ult/flash/what long CD before the event, then you'll be at a disadvantage going in. I think a good change would be refreshing all CD's before/after an event.
- Ivern's passive is useless and doesn't work on jungle camps.