I don't have MR points in Australia and my spend is not consistent high, so my priority has been a little different to most others in this thread.
I went with Hilton Surpass back when it had a $95 annual fee as I thought the instant gold and 10 visit priority pass effectively made it a cost neutral card to hold indefinitely. Amex clearly agreed with my view and decided they were giving away too much value - around half a year after getting it, the PP benefit was nixed and the annual fee increased.
To counter this, during the transition period to the new surpass product, I decided to get a Hilton basic amex - the thinking being I may as well apply for that and secure the sign up bonus before I eventually downgrade the surpass to a basic (you obviously don't get a bonus for downgrading, and once you've downgraded to the basic you can't get the sign up bonus for the basic card with a new application anymore either. Also note that you can hold onto two basics, so my thinking was that I could retain them both at that level and age both accounts indefinitely).
A year on, I haven't actually downgraded the surpass as I've found the new quarterly $50 credits to be fairly easy to use up, but I was itching to do something so I ended up applying for the IHG premier with Chase - again the thinking being at $95 annual fee, a good sign up bonus and a free hotel night annually after that effectively means it is a net zero cost card to keep.
What's next? My ultimate goal is the C1 VX, which I regard as being the ultimate net zero cost card - it may not earn the most points, but it is a decent all rounder with some great ongoing benefits, meaning I can almost use that as my day to day card for everything and get a decent earn everywhere. This one is proving hard to get, especially as my credit score has stayed stubbornly low (at the "good" level), plus some of the feedback from others here about C1 is making me nervous. That said, I'm still going to aim for it and will switch back to Aus churning in the meantime.
The cards I got has opened me up to the world of hotel points earning. You don't have nearly as many chances to get outsized value, but given the way airline devaluations are going (plus a healthy stash of qf and va points still), I'm not feeling like I'm at a substantial disadvantage holding onto these cards as opposed to flexible currency cards. IHG and Hilton have both treated me fairly well - I've received modest upgrades on almost every stay with the status conferred with the cards.
Your strategy really needs to be tailored to your lifestyle - how much you're willing to spend each month, how regularly you want to churn, whether you want to build a strategy for your Australian MR, etc. My approach has been far less ambitious than many others on here!
