I'll play the devil's advocate and argue the other side.. The two year limit was put in place for a reason. It was to separate the short term traders, who do a lot of market manipulation from the long-term investors. By locking up around 95% of the Steem in a 2 year contract, the overall market cap is able to remain a lot more stable - which is needed in order for everything to work. If the entire market cap of Steem was a liquid asset that people could buy, hold, and then dump huge volumes of Steem at a time. The market manipulators would be able to run the show.
RE: My proposal: reduce the withdraw channel from 104 weeks to 104 days or even 104 hours to make steemit less like a ponzi scheme