Please help with setting up a streaming system

I'm investigating the same options at the moment. I like to understand what I'm doing from the ground up. "Buy what works for me isn't much help although none of the suggestions are bad, they just don't help as everyone is unique and their need differ. I started off reading John Darko's BACK TO BASICS Part 1: Music streaming guide and worked up from there. https://www.youtube.com/watch?v=E5rGHPYh3E0 

Bluesound is the typical entry point. I would recommend Cambridge Audio CXN 60, for roughly $1100. Sounds great (it also has a good DAC, but you can bypass it and use your own). You can play Tidal and Qobuz directly through Ethernet or WiFi. It does Apple AirPlay and Google Chromecast, so you can play anything from an Apple or Android device. It is really good with Internet Radio. The app works well on either Apple or Android. Customer service is quick and responsive, not that you will need them very much.

Cat 5 is sufficient.  You may get very slight uptick n sound with higher but not enough to justify rewiring the house.

Your iPad will work well as the controller for a Bluesound Node, that's how I stream Tidal in my living room system. I use an iPad Mini because the size is perfect for easy handling but with a screen large enough to be easily read. It also works well with a WiiM Mini streamer in my office system. The WiiM Mini is another excellent way to get started with streaming. 

https://wiimhome.com/WiiMPro/Overview

If the cat 5 isn’t sufficient

Cat 5 is fine

Everyone usually recommends the one they use,

I use five. The Bluesound Node for MQA, the X-Box Series S for streaming music videos on Plex TV, Qello Stingray, or YouTube, also for streaming Atmos music from Tidal or Apple music, The Sony UHPH1 for streaming DSD and SACD, and finally my Paradigm Link (which is very similar to the Martin Logan Unison I recommended and has ARC). I don’t own the Unison but recommended it instead of the Link because it has ARC and also does Airplay.

OP, most of these streamers limit what you can stream. If you want to stream a service not in the OS you are screwed. The Unison will work with Spotify, Airplay, the Play-Fi app or DLNA. This app has one feature that makes it the winner in my system. If you use a windows tablet or PC and use the playfi windows app anything you play on the PC is streamed. I like services not on most apps like mixcloud, soundcloud, and concert streaming services like wolfgangs.

That is why I prefer the OS. The reason I prefer the SQ is ARC, no other streamers offer that feature. Finally its 50% off, a winner.

IMO, a new or used Innuos, Lumin or Auralic would put you far ahead of of the Blue Sound.

I'd also strongly recommend the Uptone Audio EtherRegen switch (to get rid of jitter-causing noise) placed just before the streamer. since the rest of your rig sounds pretty solid.

You could probably do both for a total under $2k.

Then some day spring for a newer DAC.