RD only free if you have a "pro" version of Windows. Otherwise, it is ~ $100 for a seat license which is perpetual unless MS has changed that also.
RD is my choice also given the price and the fact that the other options are all built on it. The only downside to using it on a PC in the office connected to the LAN is that you need a physical person to reboot (unless they have incorporated that) and if the PC goes off, you need a physical person in the office to go turn it back on. Clients that support multiple logins, usually run a server to host the desktops rather than relying on desktop PCs but both work fine. One of my clients had a bunch of remote workers and the manager had a rack of PCs in her office connected to a single monitor and keyboard
RD connected to an office desktop runs on that PC so whatever performance you get is dependent on that PC and the LAN. RD hosted on a server, generally provides the best performance since the BE is normally on the same device as the FE which eliminates the LAN latency.