'Better' could cover a whole host of requirements.
For some folk a fully 'integrated' device with network capabilities plus analogue and digital inputs in a small form factor will be more than ideal - most of the big brands now have 'affordable' options inc Arcam, Yamaha, Marantz, Denon etc (Note - most miss off USB support).
For some 'flexibility' will be more of a consideration and being able to mix and match a USB DAC with a Stereo Amp is more appealing as it gives you more choices in the long term, though you can end up with a tangle of box's, wires and power adapters and a never ending 'search' for the perfect combination.
'Duplication' does tend to come into most systems as you end up with a mix of multi-capability devices so having a system with a single DAC stage could be tricky to achieve. I guess it would be seen as a 'challenge' for some
'Network' playback would be pulling content to the streamer over your network (wired or wireless) and the streamer then decodes the content so unless there is an issue with the network the fact you are using WiFi will have no affect on what you hear - though you may be pulling lower quality streams, depending on the service you use, which will have an affect on what you hear vs. say a CD or non-compressed rip on a local server.
'Bluetooth' playback is what a lot of folk are using and it is a compressed format (see note above about the content stream you start out with also affecting what you hear) - even so many folk are more than happy with how it works and you have the option to look for aptX (or similar) enabled Bluetooth devices to ensure a higher quality connection.
Worth considering -
iFi Audio Zen Blue Bluetooth DAC Review
Loudspeaker and room is still a key consideration to the final sound you will hear - as is the amp to speaker relationship if you have a large room/inefficient loudspeakers as most of the 'integrated' streamer devices are assuming you are looking for a relatively compact package and will not be aiming for huge SPL levels.
Which music services will you be using? How are you using the system - desktop or more conventional 'lounge' layout and if the latter it is always good to start out with a room and seating layout and then work back towards suitable amplification for the preferred loudspeakers.
Joe