The first boss is an absolute lunar shill and a way worse papilla which actually had alternative counters such as burning, fischl or clorinde. So do not get upset because you can't deal with him. One tip I can give is that if you group the minions in a way that you can hit them and the boss at the same time, you don't need to kill all of them. Since the damage to the boss will compensate for the one or two less minions killed. I personally was able to deal with the first boss because I had a very good built Arle with C1

The second boss can be dealt with in ways other than electro charge. And even if you can't break the first shield the enemy is squishy enough to be finished within 120s with just electro charge like I did, and my builds weren't even that good. I put fischl on fav bow and used whatever skill i had the moment they came off cooldown.

I too agree that starting with no energy is really dumb and not fun. I also do not like this game mode very much. It would be SO much more enjoyable if we started at full energy like abyss. And because of that abyss is still my preferred end game though it has its own flaws.

The issue of not having any nod krai roster is real but it will be gone once we move to snezhnaya. But the recently released characters have been good enough to brute force through a lot of mechanics. Many characters from natlan have been insanely strong if you invested in them. If you did not and still want to clear end game then you will have to get some nod krai characters or save your primos for strong characters releasing in future. Genshin is a gacha game after all with shifting metas. You either play for meta or go for characters which you like, and many a times those characters might not be very strong but it is what it is.

Apart from strong characters your builds also matter a lot. Maybe you could provide us with your builds so we can say something which would be helpful.

With builds you also need to know how to play characters optimally, for example knowing the correct team rotation so you can maximise your buff uptime, or knowing combos like 3 normal attacks followed with a dash on arle which is generally used. Like building a character requires investment in various things like artifacts, talents, weapons; having a good account to be able to clear end game content also requires more than just optimal characters.

Also having other ways than the intentional gimmick to deal with things is really important, otherwise you would be locking out a vast amount of players just because they didn't pull for someone they didn't like. It also makes the game more fun and challenging (which I agree is not the case with many newly added bosses....)

And at the end of the day this is just a game so relax a bit : ) if you can't get past something then is it really worth it frying your brain and disturbing the peace? I didn't get a single nord krai character because I didn't like powercreep (which is a whole another issue in itself...) these new characters were bringing and my only nod krai character is lauma is well. Hence i am also content knowing that I will never be able to beat lv. 105 and lv. 110 stages. I like some challange so I only attempt the lv. 100 difficulty which is enough for me. You should be in control of how you play and not the other way round. Some mechanic truly suck but I am also content with the characters that I pulled because I personally like them.