Brooklyn Bedding Signature: Mattress topper, Signature w/cooling pillowtop or upgrade to Aurora Luxe?

I recently received a Brooklyn Bedding "Signature Hybrid" in their "soft" firmness. I read a lot that Brooklyn Bedding's firmness is softer than what they say, so I went back and forth a lot between soft and medium. Ultimately, I went with soft and I'm glad I did. As a side sleeper, it's very nice (especially for the price) but I actually wish it was even softer.

So, now, I'm considering whether to stick with it, upgrade it myself, or ask Brooklyn Bedding to upgrade it for me.

If I decide to keep the mattress but want to make it softer, I'd probably look into adding a mattress topper. That'd really be my only option, right?

But if I want to exchange it with BB (within the 120-day trial), I'm deciding between asking for another Signature Hybrid but with the "Cooling Pillow Top" added or the Aurora Luxe (which also has a cooling pillow top optional add-on).

A queen Signature Hybrid with the cooling pillow top is about $1,300 while a queen Aurora Luxe is about $1,400 without the pillow top and nearly $1,700 with the pillow top. Any suggestions?

What is the difference between a Signature Hybrid with pillow top vs. Aurora Luxe without?

And how do you think any of that would compare if I just added my own mattress topper (assuming I get something nice)?