Al frames are "harsh" becauase Al tubes are fat, because AL will fatigue if bent, so designers make tubes that are stiff enough not to bend. The low density of the material ensures that the weight penalty of the extra metal is not significant.

High-end Al frame-builders like Principia make frame that are a little more comfortable and finely tuned. They seem to be the frame of choice for European pros who have to buy their own bike.

There are some great Ti frames around, like Airborne, that wont break the bank. How they last compared to a Merlin or Lightspeed, we can only wait and see.