I'd be more worried about the House than the senate in 2022. There's 20 Republicans and 14 Democrats up for reelection in 2022. I'd say 3 Democratic seats are at risk. Georgia, New Hampshire and Arizona. Kelly looks good and could win easily. Warnock a slight favorite, Hassan, NH will probably face the current governor Chris Sununu which is well liked. Higher approval ratings than Hassan. Meaning 50-50 or slightly favoring Sununu. NH might be a Republican gain.
Three Republican senators are retiring, Burr, Toomey and Portman. Burr NC and Toomeny Penn retirement makes those seats at least 50-50, perhaps in Penn making the Democrats a slight favorite to pick up that seat. That a possible 2 seat gain for the democrats. Wisconsin may be another gain for the Democrats. Georgia, it all depends on who the Republicans choose as their nominee. If it is Walker, Georgia Bulldog and NFL star who wants to run as a Republican, perhaps making the GOP a slight favorite over Warnock. If someone else, Warnock would be favored.
Portman's retirement in Ohio still leaves that state as a GOP hold in my book. All other seats are solid or safe for the party that holds them.
Bottom line Democrats, 2 at risk with a possible third in Arizona. Republicans, three at risk. So there won't be much of a change. But the odds would favor a 1-2 seat pick up for the democrats. Could be another runoff in Georgia, Warnock vs. Hershel Walker which all depends on the Libertarian candidate who usually gets 2-5% of the vote down here.
The House, who the heck knows until redistricting takes place. The latest generic congressional poll, Democrats 47, Republicans 42. But that is nationally, which means little. It's one district at a time which counts, not nationally. Until the new districts are drawn, any speculation is a waste.