I have 300K points and I want to know what would give me the best bang for my points. I would rather only use about 200K points, but I am flexible. As for airfare, I have 50K AA miles (vacation for 2). I want to go to a beach destination outside the lower 48.
Where to go? What to do?

Get a travel package before January 15 when the changes (mostly devaluations) to Marriott Rewards take place. A category 7 property award for 7 days is good for a week at one hotel. This costs 150,000 points, and you can get another 120,000 miles on AA (or many other carriers) for another 120,000 points. For a category 6 travel package, the hotel certificate costs 130,000 points, while a category 5 hotel certificate for a week costs 115,000 points.

Start looking for places where you would like to go and check for availability. You can order a travel package without attaching the hotel certificate to a specific property, but you must order by January 14 for the current redemption rates. The hotel certificate will be good for a year after its issuance, and you can attach it to properties for stays after January 15. However, if you have your eye on a property that is changing to category 8, you must book the reservation before January 15. Marriott's reservations extend about 48 weeks ahead of the current date, although some properties load in less inventory (award and paid). If you want a specific date that is not yet loaded (and is close to being about a year out), you can ask if the hotel will provide room inventory.

If I get a 1-5 travel package, can I still get back 45,000 points if I don't use the hotel?

You can that back as a credit, but it would be a big waste of points.

It'd be more of a waste to do the Air Mileage Reward. If I wanted 120,000 miles from that, it would cost 310,000 Marriott points. If I did the 1-5 package and then credit back 45,000, 120,000 miles would cost 190,000 points.

You could probably trade your room certificate to someone else for other stuff that would have more value. There are resort properties in Thailand that would need only a category 5 certificate.

The travel packages changed a while back and now you only get like 15K miles to redeposit the entire week. Hardly worth it - you could use even for a day or two stay and come out ahead.

But to answer the OP's question - I would still do a travel package - depending on the category hotel you want - 235K for 1-5, 150K for 6 and 150K for 7. With that you could get 120K miles on AA, UA or DL.

Billy