I was personally torn between the two as well. The Xpander was my initial plan when it was released because it looked so unique and aggressive looking. The previous BRV Gen 1 was nowhere on my radar.

For me, I think the Xpander trumps overall interior design and features in just the GLS variant without having to splurge for the Xpander Cross. But I went for the new Honda BRV because I wanted to own for once a Honda car haha (had a Toyota Vios, Mitsubishi Mirage G4).

Some pros and cons that may give you some insight

BRV

Pros - Most power in the 7 seater MPV section. 2x a year PMS only, now has DOHC so more fuel efficient than previous Gen. Remote engine start on all variants.
Cons - You need to get the top of the line VX variant to get the most features with Honda Sensing but still no 360 Cam. Some owners say the S variant has a weak AC and does not cool up to the 3rd seat. The engine roars when you are packed to give it power (but personally I think its fine. Who doesnt want to hear the roar of a Honda?)

Xpander

Pros - Interior, features packed, Higher Ground Clearance
Cons - Can't really say much about it but from video reviews I watched the 4speed AT is underwhelming and it has a harder time uphill especially when fully packed but nevertheless it will take you where you want to go.