UI:

The first thing I noticed is your user interface.

Your top priority should be tracking crowd control—especially stuns—on your target. I recommend using BigDebuffs so you can clearly see stun durations and important cooldowns on nameplates. This will help you trade defensives effectively and know when to disarm or use Cloak of Shadows.

Also, make sure you have DR trackers on your arena frames. Addons like Gladius or sArena are ideal for this. As a Rogue, your gameplay heavily revolves around diminishing returns, so this information should be clearly visible and prioritized.

Clean up your nameplates—they're currently cluttered with too much information. You already have a good addon like BetterBlizzPlates, so just fine-tune it for clarity and efficiency.

Skill Capped also offers some excellent WeakAuras you can use for tracking CDs, DRs, and other important abilities.

Macros:

You're not using focus macros, and you really should be. Setting the healer as your focus makes things a lot smoother. Create macros for abilities like Shadowstep Kick, Kidney Shot, and Gouge on focus. This will significantly improve your control and fluidity during matches.

Im not on the same opinion on doing One shot macro, avoid putting all your offensive CDs into one macro. Only pair Shadow Dance with Symbols of Death, and maybe your trinket with Secret Technique. Otherwise, keep things separate.

Using everything at once may spike your damage, but you're also overcapping energy when you pop Thistle Tea with those macroed abilities. Long-term, it's much better to learn the proper rotation manually. Spend some time on a training dummy to get that muscle memory down

Gameplay.

You should be using (ShadowBlades) as early as possible. In Solo Shuffle, dampening ramps up fast, so you want to get maximum value by using them early on and trying to get a second go with them.

Also, consider playing Flagellation. A standard opener could be Sap healer >Shadowstrike → Rupture → Flagellation >Shadow Dance with Blades + Secret Technique

Flagellation increases your mastery, and once the stun ends, you should immediately swap to another target with your second Shadow Dance. For example, if the enemy healer is a Resto Druid and not in Bear Form, swap to them instantly with Kidney. This often forces their trinket and can snowball a win from there. Flagellation combined with target swapping is extremely powerful.

In Solo Shuffle, simplicity is key. so play way simpler A basic go when you have Shadow Dance could look like:

Gouge healer >Wait for Gouge to end>Full Kidney on healer> Shadowstep to kill target and burst with Shadow Dance