It's been a week. If Hill Republicans asked me, I'd have one short-term, and one long-term, piece of advice.
Short-term: in your newly super-sized conference, you have between one and five Enid Greenes and Eric Massas. That's what you get when you win a landslide. Be ready. You really don't want it revealed a couple weeks before an election that the leadership knew for months all about whatever bizarre misbehavior they engaged in, but looked the other way.
(Worth adding here: no, having Fox News and the rest of it on your side won't do much good in those situations).
Long-term: yeah, I know, Republicans don't think they have any long-term problems right now (which is, of course, itself a problem). In fact, however, my advise to GOP leaders is to think long and hard about some seriously screwed up incentives within the Republican party network. One is that for a lot of Republican-aligned pundits, yakkers, media outlets, and others, it appears to be far more lucrative for Republicans to be the out party than to win elections. The other is that there are strong incentives for almost everyone within the party to always seek room on the right. Neither of these things are a completely bad thing -- they brought enthusiasm to the party in the face of disaster in 2008, rather than the circular firing squads favored by the other party whenever it has a setback. But it is a significant danger, and winning is apt to make the second part of this even worse -- despite the warning signals in several Senate contests.