Although stealth delays radar detection, its more important role is making stealth planes hard to target with weapons. The wide bands of radars that can detect the planes are not able to locate them accurately enough to target them with weapons. No stealth is invincible, so mission planning is also key.
The F-35 is vastly superior to the Gripen E. By comparison, the Gripen E is the budget choice. If the goal is to limit dependence on the mercurial United States, the Gripen is dependent on American parts.
The U.S. may not have enough pilots to win a long war against a peer competitor. It takes a long time to train pilots, and they don’t stick around because flying commercially pays more. The pilots we do have don’t get enough flying hours. The U.S. Air Force has similarities to Japan and Germany’s air forces at the beginning in WWII. Germany and Japan did not have enough pilots or a robust enough pilot pipeline to maintain skilled pilots throughout the war.