I upgraded to the platinum membership mainly because of the 10% discount on reserving "last call" deals. I booked 2 weeks so far this year, and the 10% discount has amounted to something in the neighborhood of $50. I will probably book another week for this summer. The total amount of savings might not add up to the additional annual cost for the platinum membership fee, but could if I book more weeks in future years.
If you do not use all of your points, maybe saving them for something big later on to spend them on, platinum membership allows you to extend unused points for 2 years instead of 1 (for a fee of course - same fee as non-platinum members pay for 1-year extensions).
Also, for other special deals (sales, similar to last calls), platinum members get a one-day advance notification, and they can view the sales a day in advance of when the non-platinum members see them. I have not taken advantage of this yet, but it might come in handy some day.
Your original question was whether platinum members are able to see resorts in addition to what non-members see. A previous poster noted that there are some things available, but I have not checked those out because I have not been interested in those yet. As far as the usual timeshare resorts, I don't think any additional are available for platinum members (at least I have not discovered it yet if you can). The only thing I know of related to that inquiry is the one-day advance notification of sales.
There are other "perks" of platinum membership, but I either don't care about them or haven't investigated them yet.