noiasca:
if you don't like WiFi, use a Ethernet Shild and
a dedicated 3G/LTE Router or an USB router with 3G/LTE stick.
That sounds sensible. I have a TPLink TL-MR3020 router into which you can plug a 3G / 4G dongle. AFAIK you just need to use a dongle that works in whatever country you are using it.
...R