I decided on LibreWolf for work, Mullvad for sensitive search such as places near me, Firefox for random stuff and Tor for piracy sites. I’m currently looking to replace Firefox as well

There’s no problem with seeding. There’s actually more uploaded than downloaded

As some have stated depends on treat model. I personally use Mullvad for both pirating and accesing restricted sites in my country and evading shity laws. 5€ 5 devices with no bottleneck it’s pretty good. Sometime I use tor when I try to reach a site that the WiFi provider has blocked

Phones listen but not on the way you think, I’d say they just listen for keywords the same way it listens for “hey Google” also who knows maybe he searched it beforehand or is a fan

If you’re using Mulvad it has DNS content block

You want two VPN connection at the same time? I’m not sure it’s possible