I would allow a suspended person to provide directions regarding the disbursement of their property for the same reason I would allow it for a deceased person: to do otherwise would be immoral to me.
Looking strictly at the mechanical aspect, suspension requires a capital investment, and the only possible return on that investment is to preserve a brain pattern or entire body. As opposed to, for example, murdering someone considering suspension and giving the money they would have spend on suspension to entrepreneurs with good ideas and business plans.
Yes, there is a certain amount of economic activity which results in the suspension; but all of the labor and materials used in the suspension would otherwise be available for other uses, without diminishing the economic value of consumption.
Looking strictly at the mechanical aspect, suspension requires a capital investment, and the only possible return on that investment is to preserve a brain pattern or entire body. As opposed to, for example, murdering someone considering suspension and giving the money they would have spend on suspension to entrepreneurs with good ideas and business plans.
Suspension as practiced is not like that; there are more capital investments than the mechanical. You really don't know anything about the trust funds?
Imagine you accept the main idea of cryonics, that if we freeze brains future technology is likely to be able to extract the encoded information and revive the person digitally. [1] While this currently costs about $120K/person, if we did it routinely to everyone it could probably get down below $1000/person. Which is interesting: the current cost of averting a death is around $1700, but someone who doesn't die of malaria is still going to die of old age, so you can't really say their death was "averted". While someone who is revived after being frozen wouldn't live eternally, they might get to experience thousands of years of subjective life. In terms of life-years, getting cryonics to be really cheap and paying for people to get it sounds like it beats GiveWell's top charities.
Aside from not agreeing that cryonics is likely to work, however, I don't think the value is actually all that high. A future world which would revive large numbers of people we freeze today would be massively different from the current world economically, but would still have constraints. There would be some number of digital people that could run simultaneously on whatever people-emulating hardware they have. Preserving additional 21st century minds would give future people the option to run revived people instead of new people, but I don't think it affects the overall number emulated.
[1] I don't think this is likely.
I also posted this on my blog.