“And that’s great, but the Senate won’t impeach and Wray will keep his job and become even more vindictive. “
You mean the Senate won’t convict. The House can impeach, though. As for Wray, a vote of contempt of congress against him will sully him, even if he keeps his job. He will either end up cooperating with Congress in other respects (unlikely) or go aggressively on offense, which might well be his undoing. The Watergate break-in didn’t do in Nixon. The cover-up did. Of course, back then people in government had a conscience, wanted to become a real boy. Jiminy Cricket has been squished by a naughty puppet made in China.
A vote for contempt is the most severe action the House can take because it puts the decision to prosecute at DOJ. Garland did with Steve Bannon. He won’t with Wray but it does illustrate his hyper-partisanship. An impeachment is symbolic for reasons you mentioned but is toothless.
I repeat, the strongest action McCarthy can take is to get the entire GOP caucus to vote for contempt and refer it to Garland.