One thing I agree with the Weng on in recent times is the weakened hold that the CL has financially on clubs as rich as ours, so I don't think that's the main dilemma, so much as the continued decline of the 'image' of Arsenal as a top club that can attract and keep top players etc.
United have survived a couple of seasons (?) starved of the CL oxygen supply and they've still signed Pogba/Zlatan/Mkhitaryan in the interim. Okay they have more clout than we do in the football food chain but we aren't far behind.
We'll be okay in the Europa for a season or two, it's more about can we convince top players about our ambitions to get back in over the next 5 years and the success we're building for post-Wenger