Who else goes out of their way to oppose the lefties and righties? Of course I lean a little bit to the the green and libertarian side, so I am not strictly moderate. The Moderate Party espouses the following ideals and platforms, among others:
Oppose extremists from either party. The correct politician is one with a proven track record of voting against their party on key issues. Even if someone leans away from my libertarian and green impulses, I will still vote for them if they seem likely to vote against their party. The only worthwhile politicians are the ones who are willing to stab their party in the back and betray their own most deeply held values, again and again.
Oppose gerrymandering. Voting districts should be determined every ten years by a computer algorithm that creates the most geographically compact districts.
Eliminate primaries. Run the presidential election like the NCAA basketball tournament. Each state nominates one candidate according to its own rules, plus one for DC and one for the combined territories. The remainder are awarded to a few states in proportion based on population, 64 total (perhaps 52 so people have less to consider in the first round). Then the country is split into four parts with approximately equal population (geographically compact by state lines) and the candidates must campaign around the country with the highest-voted half progressing to the next round. At the end the last four candidates are voted on by the whole country, and then the best two if nobody gets above 50%. The whole process will take a year, November to November. Presidents can serve unlimited non-consecutive terms, but they have to go through the wringer each time.
Plenty of other moderate platforms exist, but in general they are centered around fixing inefficiencies, correcting injustices, simplifying complexities, internalizing externalities, and the like. And always vote against extremists who know the solution to any issue without even thinking.