Actually, I do think that you can do this. Note that SSIS installations are not "instanced" like the rest of SQL Server, however, the execution platform actually needs very little in order to run SSIS. In fact, all it really needs is the DTExec.exe image and the RTL's to run it, it doesn't even need a SQL Server installation (if I recall correctly).

And the SSIS Service is only used for storing the packages into SQL Server. If you store your packages to the file system instead, you wouldn't need that piece. The package deployer/installer is also optional, I never use it myself, I just copy the packages to their file store directories.