You say:
> No sublicensing (e.g. incorporating part of it into your own program)

It is true that the Elastic License doesn't allow sublicensing, but 
disallowing sublicensing doesn't (by itself) disallow incorporating part 
of it into your own program. GPLv3 *also* disallows sublicensing 
(section 2):
>  Sublicensing is not allowed; section 10 makes it unnecessary

And section 10 says:
> Each time you convey a covered work, the recipient automatically 
> receives a license from the original licensors, to run, modify and 
> propagate that work, subject to this License.

ELv2 doesn't have a similar clause to section 10 of GPLv3, but it 
doesn't really matter in the case of Apollo's ELv2 products, since 
Apollo already grants *everyone* a license to the covered products 
subject to ELv2. Downstream users, relying on the license in ELv2 to 
"prepare derivative works of the software", would of course still need 
to comply with the ELv2, meaning that if software that incorporates ELv2 
software, you would be unable to sell the parts of it that are based on 
ELv2 code (among other restrictions).