Battlefield from Atlas is great, 11 issues and packed full of great material/covers. There's a collected volume. Battlefront is another that is pretty great from start to finish, but a bit longer. It catches the early stuff and the later stuff when Sinnott, Severin, etc., were at their finest. If you want the full spectrum, Battle starts in the early 50s and then ends with Kirby/Ditko pre-hero Marvel stuff. It's got everything from Atlas, but the later 50s stuff isn't as high-yield.
Outside of Atlas the EC war stuff is pretty good, it's a little more uniform IMO, so getting a few representative issues makes more sense to me than completing a run. The same applies to Farrell, although the shorter runs make completing them easier, but they all kinda blend together. Exciting War from Standard is a favorite of mine, and Battlefront from Standard is only one issue that's great from cover to cover so that makes an easy run to complete. There's one coming up on HA (https://comics.ha.com/itm/golden-age-1938-1955-/war/battlefront-5-standard-1952-condition-fn-/p/122421-33001.s?ic4=ListView-Thumbnail-071515). Foxhole is 5 issues, but they're all now 4 figures in rough shape.
IMO, Atlas stands out above the rest in terms of quality.