I market pretty heavily on twitter; the current detection they use appears to be the mass-unfollowing of people.
A couple of months ago my accounts were banned pretty constantly, I narrowed it down to be the unfollowing to be causing bans. I turned it off, and have been doing ok.
If you need to follow more people, simply open additional accounts.
I have opened hundreds of accounts and added ~1900 people on each, all from the same static, dedicated IP. I haven't been IP banned and as far as I can tell I haven't had very many accounts banned either. Obviously, your mileage may vary.