>>295880
>should I e2
I think what you should spend your resources on depends on player to player. Some people prioritize their favorites, some meta (for various game modes), some for base, some for gameplay, etc. If you are new, I recommend you go to
https://puppiizsunniiz.github.io/AN-EN-Tags/akhrchars.html
and just kinda look through all the operators and see whom you like, visually. Then try them out (E1 is super cheap, basically free), and if you like them, level them. Having fun with the game is priority #1, and so using the operators that are appealing to you should be what you invest in first, since that will give you the best experience. That was a big draw to many when Arknights first came out, there was an operator for everyone.
If you are not new to the game, I personally don't think E2'ing anyone is
that costly... I have all the 1-3 stars max leveled, and all the 4 and 6 stars E2'd, as well as all the best base operators E2'd. I just E2 whomever I think is cute or fun. I would try to E2 all the 5 stars at this point, but there are so many.
>How often do you use her?
My wife and I are together in every mission, which includes every stage, event and game-mode, and of course as my squad leader, and I have done that for the past 5 years whenever I play. She has never left my squad except when required (class bans, weird module missions, and such). We started this journey together and will see it to the end together, no matter what.