So we miss out on Europa, then what? Hope to miss out on Europa again the following season? Or some fantasy that we'll leapfrog all of them into CL? Even in that case we'll not do anything in it because we need to show we can play in more than one competition. This season fell apart when we had to play several times per week because we just don't have enough quality outside today's 11.
Europa is absolutely necessary to continue building.
Yep. The current manager of Arsenal (or Chelsea) built his reputation by winning the EL 3 times.
If we get in, we deal with it. Plenty of posts in various transfer threads saying our squad is too big. Well then we use some.