Thank you very much for the excellent response.
I saw that you can get PC plat by simply getting the branded credit card so I'll look at that as a backup plan.
I've looked into RA. You can get one off of ebay for ~$500 plus $200 Ambassador membership. Not a bad deal if you're planning on a number of nights in an Intercontinental. I like/hate the free minibar concept - my liver can only take so much damage.
I've filed that strategy away for future use.
You were reading my mind on a non-match/challenge strategy for Starwood. I could easily bag 25 stays over a 6 month block of time.
But that's the same number of nights to achieve Hyatt Diamond without a status challenge.
Thanks for the Hilton assessment; I am now leaning hard toward a Diamond challenge from Hyatt. My one problem is that they will probably require me to have x number of nights in my recent history prior to giving me a Diamond challenge. I wouldn't 'burn' the branded credit card just to get Hyatt platinum, as the credit card gives 2 free nights BUT gives 2 free nights in suites if you're already a Diamond. I can't find the suites for Diamonds listed anywhere anymore so that may have expired.