Term limits for congress members is essential for the future of our democratic system. It impedes the revolving door of lobbyists and politicians and the corruption that accompanies it. Term limits would stop lobbyists from easily attaining a relationship with a politician because of elections putting new members into political positions and obtaining new ideas. The corrupt under-the-counter deals would be lessened because of constantly changing congress members and short terms not allowing for strong attachments to a certain person or company to be made.
While I agree with you that corruption in Washington is rampant and that Corporations aren't People (They're a place, or a thing, and therefore shouldn't have a stake in the political process...), imposing term limits on Congress can prevent the wrong person from taking (Or staying in) Office. An alternative to term limits is to lower the minimum age at which one can be elected to the Senate or House Of Representatives (30 and 25 is too high, with advances in society and technology taken into account young adults living in this day and age are much smarter than those coming of age in the late 1700's, when these limits were instituted...). If more young people were involved with the political process, it'd be harder for Lobbyists and Corporations to buy their way into DC, nothing in life is perfect but this would result in rampant corruption tapering off (Ted Cruz, Bernie Sanders, and Donald Trump are the 3 Candidates favored most by young people in this Election. To some degree, all of their Campaign's platforms involve an element of clamping down on corruption in Washington. Coincidence??? I think not.....)