Knight-Enchanter can solo the game on the hardest settings, so you don’t actually really need companions. If you’re looking for builds though, I’d go hard into high-DPS builds because you’re the tank. Sera and Varric are both archers so both do ridiculous damage. Sera works particularly well without actually being controlled. Cole with a bow is also dangerous as hell. After that you’re looking at various casters, with Solas generally the best all-rounder. If you want a second tank for some reason (I have no idea why but there are a couple of fights where it might be nice) then Blackwall is ya boi because he’s the only melee who is genuinely good at not dying.