If it was me, I'd get a 7wt or even an 8wt for bass and steelhead (and salmon and pike) to ensure I could cast the larger flies and have enough backbone for the larger fish. Then I would get an 8.5ft 5 wt for the resident trout, panfish and smaller bass. I think this would provide a more useful and enjoyable tool in each situation.
The trout rod would not have to be a Sage as there are many choices for the lighter rod as they do not need to be so stiff.
I would also suggest you look at a Redington CPX which is designed by Sage but built overseas. I have 15 rods and two of them (7st & 9wt) are CPX and they are among my favourites for comfort and quality.