The interesting thing with a Republican Senate, is that Biden will not be able to pass any progressive legislation. Just return the nation to normalcy, with the policies and executive orders of the Obama administration. This is actually the political balance of power (Democratic President and divided Congress) that has historically had maximum economic booms. We also have several vaccines coming soon, so the pandemic should be broken.

Pretty much the worst situation for progressives who want immediate change. But obviously what the voters wanted, or they would have given Biden the Senate. Best example is Maine, where Collins won but the state went for Biden hard. The upshot is that Biden won't be able to do anything that promotes a backlash: In a way, not very good for Republicans in 2022. If Biden did get a Democratic Senate in 2022, then maybe he could pass some progressive legislation but I doubt it could get through Congress with such slim majorities.