While SPG point transfers are the best option if you have loads of SPG points, since you receive a 5000 mile bonus when transferring increments of 20,000 SPG points, you can transfer other hotel points to AA miles, which may be worthwhile if you have a ton of these points or just need to slightly top up your AAdvantage account to redeem for an award. (travelsort.com)
You can not transfer Hilton Honors points to other hotel points currencies. (upgradedpoints.com)
For those earning Hilton points or other hotel points, timeshares don't usually make much sense as they require a significant cash investment with a very limited number of destination options. (upgradedpoints.com)