Not sure what you mean by that, can you clarify? The rendering on the server is done using a regular Xorg server, it will use whatever settings you choose. If you use an xpra lossless mode (or lossless with auto-refresh), then this is exactly what you'll get on the client. Now, if you mean sub-pixel hinting, that's a different story.

I might mean that. I tried it, thought it was just what I needed except that text looked horrible. I attributed it to lack of aliasing and some quick Googling indicated that it could not be fixed.

No, if text looked horrible then this is something else, more than likely you ended up with a sub-par encoding (probably vp8). h264 will normally run in high quality mode unless you are really struggling for bandwidth, and with lossless auto-refresh you won't even notice the occasional lossy compression. With default settings, text looks just fine - I use it everyday.