What next after Audience AU24 and Siltech G3?

I'm fairly satisfied with my current cables but was looking to change/upgrade. I'm looking for a little more detail and wider soudstage without brightness/harshness. Budget is around $400 (used) pair RCA and $800-900 (used) speaker cables.

System consists of:
Sonus Faber Cremona - Audience AU24 (non E) speaker cables 2M.
Pass Labs 250.5 - Siltech SQ28 G3 RCA
Thor Audio TA-1000
Lector CDP-7t - Audience AU24 (non E) RCA
Trigon Vanguard II - Siltech SQ28 G3 RCA
Nottingham Ace Space - stock RCA

Also have Crystal Cable Piccolo RCA. Nice cable but lacks the bass weight of the Audience.

I find my Gabriel Gold Revelation MKII a big step up from the AU24 which is thin and lifeless in comparison

disclaimer I do have mine up for sale but it does change my opinion of them in relation to the AU24...
I'd second the Gabriels. The Gabriel Gold Revelation MKI (biwire) have bested many more expensive cables in my system, and likely will meet your stated criteria. That said, I don't see a way around experimenting and seeing how a particular cable sounds with your speakers/ setup. Component matching and individual tastes/ hearing can vary greatly. Since you're looking to buy used, try a few cables out and resell if they're not your cup of tea. For a little less, I also liked the Supra Sword.
Why not upgrade the Audience to "e"?
That was my first thought but I'm not sure if the "e" is worth the price difference rather then trying a different cable.
I just wired up with Harmonic Technology Majic Link II IC's and they are the best I've had against top Kimber and MIT. They are anything but harsh or bright...they are utterly transparent. They also mate nicely with my Audience au24 SC.
The Au24 may sound "thin and lifeless" in your system but I find it to be very full and liquid sounding and very good tonally in my system.
I did not mean to be harsh and maybe it should be noted my setup is all vacuum tubes, fwiw at the time we compared the AU24 with Audio Note AN-V on an all ss system and could not tell the difference.

Maybe a good disclaimer is that the AU 24 may be system dependant - or maybe it was the AN-V or both!
Tghooper - same here, the AU24 is very dynamic in my system - ss amps and Thiel speakers. I have tried alot of SC and haven't found one to better them.
No offense taken. Yes, the Au24 may not be a good match for all tube system...too much of a good thing if you will.
I am going to have to go with Philojet and the Gabriel Gold recommendation...I would keep an eye out for a used pair of Rev II's...or talk to Steve about the new entry level Radiance. You would get what you're looking for. I went down a long list of cables in that range and much higher and replaced them early on with Gabriel Gold Extreme's I still use the GG's....but now the Reflections. They are a whole different ball game and absolutely astounding, but beyond your range. Stretching as far as you can up the GG line for you IC's would be a good option.

That said, I yam what I yam and have had a lot of cables, and I thought the Analysis Plus Solo Crystal offers a lot of bang for the buck. Their Oval 9's are also good.....but best bang for buck went the Bear Labs Silver Thunder. And, if you can strecth a tiny bit, Stealth Hybrid MLT's are hard to beat at around 1k.

I have the GG's Rapture r and the sonic improvement over the non-revised version coupled with the Reflections just breathes life's musical essence into my intracellular spaces....happhappyjoyjoy.

Enjoy the tunes!
You know, if you like the Siltech G3 you could just ago on up the line depending on what's still around. i used the SQ88 for a long time....definitely got me started on alloys containing gold.
Thanks Budburma.

The problem with going up the Siltech G line is they cost alot of "G's"..$$.. :)
go with the used gg ic and the stealth mlt. good to go! happy holidays!
if you can swing audioquest sky's from pre to amp, you would get greater ss and body, with no brightness or harshness; they are very smooth.
pad venustas would also give you what you are looking for in spkr cables. don't mean to spend your money or break your budget, but with a high quality system like yours, you may be selling yourself short with those limits. but we all have a budget.