We need businesses which need BTA.
People who use BTA to save their money for 5 % yield, can easily find other way to get that amount yield.
What kind of people we want attract? the people just hold BTA and not use it, or the people use it and spread it everywhere?
The businesses on bitshares are much precious than people doing saving. I do not know whether you think so too.
Why limit the amount of exposure you can get for bitshares? If you want to change how the current financial system works, you also need to account for the savers who are quite passive. No serious investment besides maybe stocks gives >= 5% p.a, at least not in Europa and the US. Those people investing into Money market deposit accounts are pretty security minded, and would not invest into a stockmarket as it might be considered too dangerous. Bitshares may be eventually be seen as a "low risk" investment because of the automated yield.
Bitshares already has changed too many things to begin with, and now one of the most original features over other crypto currencies will be removed? Do not limit the amount of exposure we might get with this, bytemaster. At least the BitShares 101 video series must be redone then, pretty much all material mentions this in a prominent form.