I'm from the school that thinks, "it's not the tools it's the carpenter"...:) I have never cast one of the Sage Bass-Series rods but I'm more than happy with the Sage's I own.
I went through a phase years back where I practically only fished my 3&4 wt rods when I fished for trout...When I actually fished with one of my 5wt's it would feel like a club for a bit after fishing those other rods.
Personally, I prefer my 5wt"s that are 9 footers when chasing smallies and don't have any issues with casting the larger stuff with them...These bass rods of yours are just under 8' and run from 7-10wt rods. For me, I would think, a 6-7 wt rod like you mentioned above would be enough...
I actually won, back in the 90's, a Loomis that reminds me of those "bass" rods...It has a fighting butt etc except it is a GLX 9' rod and a 7wt...It really feels like a club in my hands and I have to take a little time with adjusting my casting speed etc...I hardly ever feel the need to fish with it though.
I think every rod has it's own personality, for lack of a better word, and it just takes a little work to discover it. I had a rod damaged in the early 90's and had to send it back to get the tip section re-matched with the butt...A good friend lent me a rod (Fenwick I think it was) that he had wanted to re-wrap and got halfway through it and changed his mind and stopped...I think it was a 5wt 9' rod (maybe an 8.5) and it looked sad...One section in one color wrap and the other in another...The smallies, to their loss, never seemed to notice...:) I still have this rod...It's part of the nephew's starter kit ;).
I guess what I'm saying here is that it's too bad you have a couple rods you are not happy with...That's a waste of dough for sure. Didn't you cast them at all before you bought them? You need to attend a fly fishing show where they have a casting pond, or visit a good fly shop so you can do a test run...At the Lodge I stay at they are always trying to stick a new rod in my hand, "Spence...Just fish with it for the day and tell me what you think." etc...Like test driving a car before you buy it I guess.
I guess I really don't understand this "specialty" type rod thing...Do we need a different rod for each type of fish we chase...I understand the need for different weight lines say for fishing the flats as oppossed to chasing brookies in a feeder creek, but do we need a rod for "panfish", for small-mouth bass, and another for large-mouth bass, and another for trout,steelhead, salmon, etc? I think, to a degree, this is marketing and an attempt to sell/draw in folks from other fishing backgraounds in to fly fishing in general.
Anyway...My $2.25 worth of "insight"...Good luck.
"Even when my best efforts fail it's a satisfying challenge, and that, after all, is the essence of fly fishing." -Chauncy Lively
"Envy not the man who lives beside the river, but the man the river flows through." Joseph T Heywood