>>266389030
Not really, since you're not working in VR, and there are no ongoing costs of ownership between the headsets. There's not a huge cost difference between the Rift S and Index either, so going with the headset you want first eliminates losses due to trying to sell the old headset and buy a new one later.
Now, if a Rift S or a used Vive or CV1 is good enough for anon's use case, then yes the money saved on that could be put towards upgrading away from that 3GB 1060, but really those specs are good enough for most VR games at first-gen resolutions already.