I don't have a switch (yet) but I would say the Pro controller is worth it. I'm not the biggest fan of the JoyCon controllers as I prefer traditional designs. The battery life is incredible so that alone makes it great
Yes this definitely seems to be the general consensus everywhere I look. Personally my favorite way is playing in GamePad mode (so is just like a WiiU) but the Pro Controler experience definitely has alot of advantages (like the battery lasting longer, for example), but also because the shoulder buttons are better spaced out and not so close together. (many people mentioning about the analog sticks aswell, but personally I don't find the thumbsticks on the joycons to be a problem, so I'd say both experiences are good for that part).
The Pro Controller is probably best for playing at home, but the one caveat is that it's
only really practical to use at home (as it's a bit big to take out with you, and won't fit in most travel cases). (even alot of the bigger ones) and the ones that are big enough to carry one comfortably without forcing them are just really awkward to carry. The JoyCon Grips can fit in some of the cases out there (but only just, and again don't fit at all in most). However, if you're playing with the joy-cons anyway, it's far easier to just have them attached to your tablet, so you don't ever need to bring a joy-con grip with you I tend to find. Your JoyCon batteries last longer by being constantly charged by the tablet, and the experience is like playing a WiiU that you can take with you anywhere. So I actually love doing it this way, and don't feel in any way disadvantaged by not having a pro controller out with me! (I think of it more as an added bonus for home) but I do get why people say a ProController is a slightly more superior gaming experience though, as they are extremely nice to use! (and feels much closer to what you're used to on previous consoles)