ELS requires SHV, as does OpenIV to make use of the "mods" folder. You're also likely going to want to install Heap Adjuster, Packfile Limit Adjuster, Resource Adjuster, etc. all of which require SHV.
If a mod has an ASI file, then it'll require a Script Hook. Anything that is installed into "Plugins" (likely) doesn't need SHV.