[noggin]

Hi @noggin 

I like your suggestions very much but I have some questions, so please bear with me.

1.I'm thinking using Telestar DIGIBIT R 1 HD SAT booting SatIP-Aex firmware via usb, but would any usb stick do the job?

I've no experience of USB Sticks that don't work. I usually use Lexar USB flash drives as I have never had a bad experience with them. With my DigiBit I'm actually using a very small flash drive - can't remember the brand (will be a well known one like Lexar, Kingston etc.) as it is very low profile (same size as a wireless keyboard USB RF receiver) as it is very low profile.

I am using the AXE firmware.

2.I read that this tuner is unreliable when using more than 2 tuners, did you have any similar problems with it?

I don't routinely use more than 2 tuners - but haven't had any issues when I have. My Telestars are not being used in high-demand situations though.

3.Telestar DIGIBIT R 1 HD SAT only have Ethernet 10/100 not gigabit, will it be able to handle the bandwidth used by 4 tuners?

The HD channels I receive average around 8Mbs - peaking at around 15Mbs in extreme cases. 4 of these comfortably fit within 100Mbs. Not a major issue in my experience.

IF you could find 4 different FTA 4K UHD channels to watch you might hit the limit... Realistically - you aren't going to do this...

Finally my setup would be like this 1x Telestar DIGIBIT R 1 HD SAT + 1x Separate Odroid C2 libreelec tvheadend server (so i can have a tv box running android OS or ATV) + 1x wetek play2 (because its the most versatile android tv box there is).

Yep - that will work - though if you aren't using the C2 as a Kodi box, there's no real reason to run LibreElec to get TV Headend to run, other than convenience (particularly if you are not an experienced Linux user). If you aren't Linux-savvy then LibreElec will be a good solution, but if you 'roll your own' Linux install you can run more recent versions of TV Headend server than are provided in the Add-ons Repo.