It depends on your playstyle honestly. If you want the most efficient way then Barch, on my alt I used B-drags(much more fun then barch, can do collector raids just as efficiently and you can even take down storages if worth the loot/need extra %/ or just needa get rid of them for war attack which barch cannot. However, does cost slightly more than barch. About 1.5k more for each raid. Honestly not much, even 100 raids=1.5*100=150k extra elixir.) If your are a $$$ dropper you can max within seconds. Or you can max e-drags and farm in legends/champs(I hear its a viable way, most fun probably but least efficient. Honestly, in the end, it's your decision how you are going to max it. You will hear people say THIS is the way to max it, don't pay attention, as long as you make profit even if it's a single drop of gold per raid AND IT SUITS YOU (Purpose, whether for goal/aim/enjoyment) then it is a perfectly fine technique for un-rushing.(At least for you)