But then, where are you gonna plug your Ethernet cable?

If you bought a alien spider router just to use as an WiFi access point, you bought the wrong thing.

I have that and use Ethernet cable.

I just have cables outside of walls, along the corners. And doors have enough gaps usually at the bottom to let a single Ethernet cable through and still close without any problems. It isn’t very noticeable even without drilling.

Never heard of yunohost, but… definitely not worth managing your own email server. That shit is essentially a full time job. And it’s forever ongoing full time job, with 24/365 on call type job if emails are mission critical. Doesn’t matter how much other hosts are charging, it’s worth using third party email service.