Hi,
for maximum image quality, besides setting the slider all the way up, I would check ‘Disable network-adaptive’ but leave ‘Disable multi-pass’ unchecked. I’d also check ‘frame buffering’ and ‘post-processing’. Hardware decoding shouldn’t be relevant for quality. For this scenario, you may also want to disable hardware encoding on the server, since hardware encoders are surely faster but they could encode with lowest quality compared to the software encoder, even when using the same parameters.
For video playback, I’d choose a lower quality in the slider (medium quality should be a good trade off), uncheck ‘network-adaptive’ and ‘multi-pass encoding’, check ‘frame-buffering’ and ‘post-processing’. Hardware decoding is usually faster.