I apologize if this is a bit wordy, I'm not good at being succinct with my thoughts, but you asked for feedback, so I wanted to say what I could.
I really like the idea of nightwave, but feel, overall, that it has been poorly implemented.
I think Nightwave was intended as a fun bonus to help players feel like they are often making progress towards a goal even while doing other stuff, which is a great idea! but due to the rarity/value/"MUST GET" nature of many of the rewards, the timed nature of the missions, and the lack of information on my progress, it feels more like I'm being held hostage, and forced to do chores instead of having cool extra mission bonuses.
First, what I like:
I love some of the rewards offered, as someone without a lot of money, I can't state enough how much I appreciate even the odd handout of weapon/warframe slots.
This may be kind of silly, but I honestly enjoy the random spawns of fugitives to track down. They usually are fairly unintrusive, and also quite quick, kind of like finding a dollar bill on the ground. They aren't as formal/dramatic as the stalker or syndicate and the guaranteed standing skips the constant disappointment of stalker never dropping that one thing you need from him even though you keep getting your hopes up every time he spawns.
I usually enjoy some of the lore/stories you guys have produced in the past, War within was some really interesting stuff, but whatever's going on here? Honestly it doesn't feel well presented. Generally all the announcer does is spout random things that don't really pertain to anything. I honestly am interested in what's going on, and who this Wolf guy is, but I've already gotten sick of the announcer saying nothing of value. Some people like her voice, I've nothing against it, I just wish there was more to it than just congratulating you on completing menial tasks or saying things that don't really mean anything, like "life is a cornucopia" that really doesn't mean much when you think about it.
The way the missions are presented.
What I have always loved about Warframe is the way one is generally able to pick the way they want to play. I've had a long day at work and want to relax? I can grab a tanky frame, do survival/defense and just collect some relics without having to think about it too much. I don't have much time, but want to do something? I can do a few orb vallis bounties or a capture/exterminate fissure before I leave. I want to try hard and focus something? I can do spider mom or eidolons. Even the daily login is very generous being "log in at some point in this frame and you get it" meaning you can even get 2 login rewards back to back if you sign in right before the reset. The laid back nature of the game also is nice, seeing as I don't usually get to play every day, often only 2-4 times a week.
To my best understanding, Nightwave was meant as an extra bonus where players can get bonuses while doing other things. Conceptually, I love that Idea, but I find that the way the system is currently designed far too often feels like it's trying to tell me how to play the game and how to spend my time.
Please don't get me wrong, I loved getting some friends together and doing the 60 minute survival, but as a whole. Instead of being something neat I can do while I'm doing other things, it feels like Nightwave is trying to control and dictate how I play the game. My biggest issue with this is the combination of the potential rewards, mission types, and time limits.
Currently, some of the potential rewards from Nightwave are a few special mods, and an umbra forma. I believe it's safe to call these "must get" especially seeing as there's no other way to obtain these items in the game and the forma is desperately needed. I know similar items have existed in the game before, such as the ele/status mods, but those always felt like a bonus instead of a mandatory 'you gotta get this' thing. Also the events to get those have generally been quite short, maybe a few hours at most to get most of the mods, then trade for one you're missing. Nightwave often requires me to spend hours at a time on one single mission, or makes me log on every single day to get a single mission done, this has caused the game to feel more like a chore or job than fun.
To me, previous alerts felt like "do this thing real quick and get a reward" nightwave most often feels like "do all of your chores else you're wasting your time playing this game and not getting as much out of it as you could." Even if I didn't like doing the odd mobile defense, a single mission was generally inconsequential, and doing it didn't mean much, and I was always able to skip it if I didn't feel like it.
The same can be said with the sortie or daily login. Because there's no true time limit on those, I don't feel pressured to do them. If I'm not feeling up to it, I don't have to do the sortie, or I don't even have to log in today if I don't want to, that reward will be there tomorrow.
As I said before, I honestly loved the 60 minute survival with friends, but the "do 10 syndicate missions" and "10 perfect hunts" while not hard, this feels like I'm being FORCED to do menial chores that I really really DON"T want to do and takes several hours of menial $&*^ing around that I would much rather not be doing. The "kill x enemies in this way" missions are kind of easy, but I do appreciate that I can do what i want (void missions, kuva, etc) and still work on the nightwave goal.
The biggest issue here, is that some of the nightwave missions do not align with what I as a player want to do, in fact I actually really detest doing some of them. I've loved in Warframe how there's many different mission types, but if I don't like to do them, I don't have to most of the time. My example earlier of the syndicate missions or hunts make me feel like my time is being held for ransom "you HAVE to do these on OUR schedule, otherwise all the work you've done for that item is completely wasted because missing these points means you might not ever be able to get it later!" A fine example is this week, where "you have to log in at least 5 days to do the sortie or miss this mission"
I've heard that one does not need to do every nightwave mission to get the maximum rewards, however there is no way for me to tell how well I'm doing on that. There's currently a "x/10 weekly mission" counter, but that doesn't really give me any information since it also counts daily missions as well. 10 daily missions is 10k points, 10 weeklies is 50k, that's a vast difference and doesn't seem to make any sense that both increment the counter.
One thing I believe would help give us more agency was if the players were more aware of exactly how many points were needed to max out at the end of the season.
Say for example, you need 30k nightwave points per week to get all of the nightwave rewards at the end of the season.
if I get 35k this week, next week the tracker says "you need 25k to hit the average". That gives me a clear marker for how my progress is going, and gives me the agency to make the call of "I don't want to do this mission this week" and not feel bad because I know I'm already over the average, and don't have to worry about it, or "i know I'm going out of town next week, i'll make sure to do every mission this week so I'm not far behind when I get back." Currently with just this nebulous value we don't know, I feel honestly like my hands are tied and I HAVE to do every one, even when it's just menial running around doing syndicate missions when I'm already capped and can't find anything else to do with the points. This might not fix all of the issues I've mentioned, but would at least help some of the problem.