Well, it’s true. But there’s a certain satisfaction derived from soloing content.
In the old days, but not the oldest, you had some thralls that were basically immortal. They could solve anything, even if the game bugged out. I had a lot of those, carefully selected, leveled and geared up. Skill was being able to capture them within a crowd, and doing all that. When I was bored, I simply wouldn’t take them with me. If I was farming a dungeon, where you need to speed things due to rng, they were super usefull, low maintenance followers. I could have the best if both worlds.
Now, weaker thralls. I also find stimulating aspects about having them. It’s more important than ever to select and level them closely, unless they are destined to the purge meat grinder.
But it gets old fast, you see? It’s a painstaking process, plus it doesn’t really pay, since you can still easily lose a carefully selected thrall due to a few seconds of lack of attention, to a lmid level small mob. It desincentivizes you from repeating the process. High stakes, high rewards works very well in games, but a situation of high stakes, low rewards doesn’t, and that’s the reason most people complain.
Let’s not firget the diversity we lose regarding viable thralls. Having you seen the sheer richbess of thralls the games has that we never get to use? It’s a real shame. We end up reduced to zerker and zerker like thralls, sonce tge others will easily perish. Something should be done about that.
Anyway, I can perfectly live with thralls as they are, as long as infinite stunlock goes. That’s the worse problem. That and pathfinding in crowded places. These are the thrall kilkers. Solve that and they are good enough. The high hp if thralls only setves to make up for a bad AI. A safety buffer for screw ups. Get rid of the screw ups and you can safely ditch the buffer. Level thralls for other attributes than health even, something unwise at the present.
Your three questions are intertwined. If you have a thrall you don’t need to babysit, he will do all of the above.
So, let’s take in consideration the concept of balance like @Xevyr puts it.
You can’t have a thrall so strong that it solis everything. It’s not something that I necessarily agree, but I can understand the concept and its validity.
I don’t want to leave less skilled players locked out of content. How can we reconcile these two factors. Make them deppending of the player build. If your build is thrall oriented, take it a step further. Don’t detract from combat abilities, as these players are those who need them the most, but inflict other penalties. Make them much more sensible to temperature, hunger and thirst. They can only feed on complex meals, the others barely nurturing. Alcohol ravages them. Cold or heat kills them fast. Potions inflict status effects or they have a coldown period. Make that choice permanent. If you choose that build, potion if bestial memory has no effect on you. It becomes serious. But you have a high stakes, high reward situation.
Sorry about the typos. You know the reason already. 
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