Prevent effectively permanent incumbency. 3 and 2 terms were just something I picked out of a hat, but the idea is that mandatory turnover isn't so bad.
And part of what enables lobbying is the extraordinarily deep networks superlongterm congresspeople create. This would reduce the effectiveness of lobbying, not enable it.
Actually it would increase it. Lobbyists get in when the congresspeople are fairly new and don't know much. All you're doing is creating a situation where all these people would have to start planning for a new job and most people get their jobs through connections. Guess who these congresspeople are going to go to? All term limits would do is speed up the process we currently have. If you want to make lobbying weaker you need to fix campaign finance. That's how you fix it, fix the flow of money and everything else will fall into place. You're looking for a complicated solution for a problem with an easy fix.