I wouldn't be ideologically opposed to an uncapped supply schedule.  But, I'm not sure I get the point.  I suppose replacing lost coins could help with price stability - that is, if there was a way to track how many coins are being lost.  Otherwise, it seems to me that an arbitrary supply schedule would just have an equally arbitrary effect on price stability.  Not to mention, there are other (likely stronger) natural forces other than lost coins that impact prices (technology, population growth, etc).

All this is to say, trying to pin down price stability seems like a fool's errand.  I strongly suspect that once the price volatility of bitcoin isn't dominated by a still way early rate of increased adoption and speculation, its natural deflationary nature - even with a capped supply schedule - won't be too overwhelming to achieve reasonably stable (but yes, still slowly deflationary) prices.