I play Warlock, too. Try Chamber of Starlight when it comes around. It’s very easy to do solo by standing off and killing everything before it sees you. I did it with Pulse, Sniper, RL, I think, since it was unstoppable/overload. You get an extra revive for each champion you kill, so the lives aren’t bad. You can pretty much ignore the timer, except at something like 15 min you no longer get revived. I did it in 10 being super cautious. Surprisingly, Concealed Void is easy to solo except the one overload Captain you need to go toe-to-toe with to beat.