Hopefully you’re already well on your journey, OP, but I agree with what folk have said about not sweating it and just seeing what happens. Including difficulty settings, most of which can be tweaked as you go if you find things too easy or too hard.
I personally find the game most fun when I try not to metagame and do what I think my current character would do in the situation, and don’t save scum for different/better options. And I prefer to work things out for myself and aim to play different characters in future, so even now I try to avoid too much info about paths I’ve not tried yet or about how others approach particular battles or challenges, and enjoy finding new and surprising content even on my fourth playthrough. I also find it more immersive if I don’t try to be *too* completionist: you can talk to every animal, read every note, speak to every corpse, fight every enemy, explore every nook and cranny and open every chest but when I do that I find it makes it too obvious where the limits of the game are, and prefer the feeling that there’s more that could be discovered even if it’s only often a different way of discovering the same thing. You can certainly have a very fulfilling game without doing everything, and if you start finding anything a chore I’d definitely recommend pushing ahead to something more fun instead. But there’s no wrong way to play the game, just a potentially bewildering array of possibilities that mean it may take a bit of time for you to work out what ways are the most fun for you!
Though I admit I find it very hard not to recruit every companion available, and agree that if you’re not planning multiple playthroughs that’s probably the best option to get a lot of their content, even if you tend to stick with the same party for exploring. I generally find myself settling into a core party of three (my PC plus two more) with the fourth party member being more fluid. Given the variety of ways to build successful parties and options for completing quests, even without respeccing companions’ starting classes there are multiple viable configurations depending on your own character class. And if you are willing to use and abuse Withers’ ability to change starting classes you have still more choices
