As others have said. Nightwave is great but not perfect. For me, I dont care for umbra forma, I will get one so I probably wont be able to decide where to put it anyway. But I like to collect stuff and I would love to get the armor and syandana. I might never use it. But I would like to have it. Just my point of view on the rewards.
Also if nightwave is replacement for alerts Im afraid its a poor one. I liked the alerts a lot. I never stressed about the helmets for frames. The one I want will eventualy come up. Then I can just hop in and do a 5min mission to get it. Here sure the helmet will come around eventualy. Lets just pray that it wont be the first week of a new nightwave when I dont have any creds and cant buy anything. Or maybe I used them all already on other stuff. You should really consider adding the alerts back. This two systems can coexist. Its always better to have a choice in how to get a reward. I might wait for it to be in alert or if I need it now, and its in rotation I can buy it. Mainly new players will suffer in this system I would say.
In the theme of choice, the challenges. Realy good challenges are the daily elemental ones. You get to choose which missions and so on. Maybe the ayatan challenge could be changed to farm 7K Endo instead of socketing 5 sculptures. The Kuva survival would be farm 10K Kuva and Eidolon one would be get 3 Arcanes. Wouldnt that be better?
I completed the 60min survival. It wasnt super hard, it just took a lot of time and I could not pause it. I dont have as much time as I used to. Mainly uninterrupted time.
As others have sugested, give us more challenges per week. You can ballance it by making the prestige go in 20K points steps instead of 10K points. So the hardcore people dont swim in creds and break the game or something.
Overall nightwave took all my time. I still need Akjagara prime, but dont have time to carck relics. Same with the nikana prime relics from weekend wars. I opened one so far. Didnt have time for more. Also there is prime vault. Would be nice to farm some relics and get some sets to sell for plat, but I dont have time for any of that. Hildryn should come this week and I probably wont have time to farm her either since I still have challenges to complete. And why? Because Wolf is here only for a few weeks so everything else have to wait.
Most importantly, please give feedback to our feedback if you can. As I write this am on page 17 and feel like its nearly pointless to write anything. I think am just adding to the noise. My only hope is that by adding to the noise it will get your attention and some of this will be adressed.