Apart from all the technical improvements mentioned above, I'd like to see Bryce 7 taking some more interesting and creative directions in imitating nature in terrain generation, cloud/skyscape creation and a greater range of water effects. 

I would like to see various forms of surf and large waves, spray foam etc integrated. Realistic thunderstorm clouds, tornados etc integrated. I would like to see river valleys created with the detail already there right down to the boulders at the water's edge and pebbles under the surface...  And how about really good background forests that are low polygon counts - sorta 'treed terrains'. I attach an example of the sort of terrain complexity I would like to see.

All this to free up the scene creator from the time consuming aspects of making the background look right, then we can move onto the central subject matter of the scene - the figures/objects and props in the foreground...