My dancers fight- i level them to cap and they fight- no slackers. Always make them archers so less chance of them dying.

Then i slowly eliminate lower end thralls i have if the ones i get are better.

Pets are the next to go. Sorry cats - ill keep one maybe two and thats it.

None of my thralls stay at zero- they either get to 20 and fight or they are gone.

So ideally a solo player cap is 60.

10 thralls /pets- dancers, pack animals etc

35- fighters
15 -archers - all capped. Level 10 purge shouldnt be a problem

That whole time you spent leveling them your doing it on dungeons to get legendary weapons to equip them with.