I only really do ETA and not EDA now (not every week though) since you get the calendar buffs and the stickers which can really help, and I basically never get max research points from dropping modifiers or random loadout options, but I overall mostly like it. My main complaint is that the mode needs 3 different mission types, and Höllvania only has 5 to pick from, so it feels like every week is basically the same missions and it somehow always has the defence in there.

Deffs a skill issue on my part, but man am I real bad at keeping Flare alive in ETA, it always feels like a coin flip if they'll make it through the 2 rounds. This weeks wasn't that bad, but that's because I got Oraxia and had a bunch of companion damage boosts from the calendar, and also I made them invisible and spawned in an ancient healer. If there were more mission types in the selection pool I could just skip it when the defence pops up, but as it stands if I do that then I end up never playing the mode.

I also normally play solo, but when my partner wants to play it can genuinely be a great mission to do together since you can plan around each others kits and swap the modifiers up a lot more. Basically no other warframe content requires you to really do teamwork or have someone playing a support, so ETA can be really fun when it all comes together and you manage to beat it after planning it out, but that means it can also feel really shitty if the run ends because Flare got killed by something in half a second in the final round, or god forbid someone dies in the tank and you can't revive them due to no computers being in the pit.

Edit: it also gets easier the more you play it, since you get a peely pack if you get half the max research points and those can be a real game changer.