Hi Womaz, it is not easy to pick the bones out of all the differing advice you are getting.
I am familiar with Arcam amps and CDPs, as well as Linn DS players, so I am happy to add my thoughts to your situation. Whether it helps is another matter.
PRESENT SYSTEM.
You have a good well balanced system. The Arcam amp sounds sweet, smooth and musical with a reasonably punchy bass. I like the presentation, but it is too "polite" for some. I think your speakers are a good match, with a "holographic" type of presentation, which would work well with the A85.
The CDP adds more of the same Arcam sound, and it's possible that an injection of a little more excitement wouldn't go amiss.
STREAMING.
I have listened extensively to most of the Linn DSs, and they comfortably out performed the Linn CDPs at the same price (which is why they stopped making CDPs).
While the dealer still had CDPs, I brought in CDs, had the dealer rip them, and compared the CD to the Rip, and heard the difference for myself.
I was using an Arcam DV79 for playing CDs (not a mile from the CD82), and a Magic DS blew it out of the water (which is why I bought it). Even the Sneaky DS (which sounds like a £2k cdp) was a significant improvement.
If you use something like dbPoweamp, you get a perfect rip, whereas a CDP has to read it in real time. A streamer has no motors or moving parts to interfere with the sound. There is also the advantage of playing 24 bit, which imo sounds better.
THE DEALER.
I suspect the dealer was giving sound advice, but with totally the wrong attitude. If there are other staff, I think you should seek out someone who is knowledgeable, but understanding and helpful as well....the owner/senior manager perhaps....and start again.
What components did you actually hear?
Have a clear understanding of what you want to achieve and politely see they accommodate you.
SYSTEM CHANGE.
There is nothing to say that you need to change everything (or even anything), at once.
My advice, would be for you to arrange to bring your amp and speakers into the shop, and have them connected to a Linn Sneaky and then a Majik DS, both of which should make a good difference. Then try different speakers to compare with the Quads. I would look at PMC and Kef R series if they have them.
This will give a good bench mark vs your existing system, and allow you to see a future upgrade path, if it is more than you wish to spend.
If you don't like what you hear, there is no harm done, but imo you should check out just how good DS + Arcam + Quad/PMC/Kef can sound.
Also imo the Arcam amp responds well to a better mains cable (eg. Copper Line Alpha+) from the likes of Clearer Audio, which can be sent back if no improvement is heard.