I know that there are no official windows desktop clients, but are there going to be in the future?
Additionally, I am aware of some syncthing GUI wrappers but can those be effectively used as clients to communicate to a central syncthing server running on FreeNAS?
I think he means:
Install and run syncthing on “headless” NAS, install “only the wrapper” on another PC, to conveniently access NAS’s ST instance.
AFAIK, wrappers would need access to syncthing’s installation, config files, etc. to do their job. And I believe that for most wrappers it would be limited to directories on the machine itself. Unless, of course, some wrapper out there can use network dir.
Maybe you can try to install the wrapper itself in portable mode on NAS, and have write access to that directory, and just run it from there on your PC. But I won’t recommend this path due to potential chaos that can be caused by network disconnect while wrapper is in the middle of some config update, and also it sounds bad security-wise.
I suggest you try syncthing first to understand the principles, and then ask questions. In syncthing you do not “select files”. You point both sides at a directory, and it makes sure the content is the same on both sides.