I notice HSBC doesn't make a big deal about mileage partners in other markets like HKG, BKK or SIN too. They do have them, but the conversion rates are not fantastic. Seems that Amex is much more into mileage partners and relationships/co-branding with airlines.
I suspect it is because of cost. An inhouse rewards program is much cheaper than having to pay airlines for miles.
Also, I notice in other markets they promote the "Premier" VISA/Mastercard, which is their own branding/status. This means they don't to pay the additional fees for Platinum to VISA/Mastercard.
As for the card design, HSBC standardises across the world. A new better looking design came out this year, but I haven't seen it rolled out to Australia yet. I think they are using up all their old stocks.