No-brainers for the new government
Some issues are big and scary and complicated (like war and our financial system), and I can understand how I'm not really in a position to specify expectations for how the government will address them.
However, some other issues are so straightforward (even if they aren't 'big') that I can confidently say that if the new Democratic government does not address these issues, then they will be guilty of negligent government.
I'm sure that many issues fall into this category, but here's are two issues that I expect the new government to take care of in fairly short order:
Medicalize marijuana: Marijuana should be recategorized from Schedule I to Schedule II, so that it is no more restricted in its use than Coca or Opium. This would not allow Americans to buy raw marijuana, but it would make it easier for drug companies to investigate and commercialize marijuana extracts and their derivatives. (I intend to write a full-length argument for rescheduling in the near future)
Recognize civil unions at the Federal level: According to Glenn Greenwald , Section 3 of the so-called Defense of Marriage Act (1996) "prohibits the Federal Government and all federal agencies from extending any federal marriage-based benefits, privileges and rights to same-sex couples", causing great hardship on same-sex couples. This needs to end, and Greenwald makes a good case for this being a political no-brainer, let alone a moral no-brainer.
Update: FWIW, my criteria for choosing these as "no-brainers" are basically the professed values of the Democrats (inclusion, compassion), public sentiment, and general reasonableness as "good government" issues.