Am i doing this right?

I've been looking at the Tamron 150-600mm lens.  I have enough saved for it now, but it's hard to get because apparently there's too much demand for it compared to the supply.  I suppose I could "stand in line" for it, but I'm going to just wait for more reviews.  But the reviews continue to be excellent.  I was planning to get the Canon 100-400mm L lens.

I agree for wildlife pictures, that I was mainly using the long end of the telephoto lens.  I used Olympus DSLR cameras for over four years during that time.  But at people and sports events I'm constantly changing the focal lengths.  Like yesterday, swarms of people would be close and I would grab the other camera and lens combination.  When they were further away like out in the water, I'd grab the other combination.  With volleyball (indoor and outdoor) and soccer I'm using a great variety of focal lengths too.  For soccer I like to be by the goal where I'll use the wide angle lens.  If the action moves further away in the field, then I can use the telephoto lens.

Here's one photo yesterday which shows one of them using at least three cameras with lenses attached.  I don't know if they are zoom or fixed focal length lenses, but he's ready.

Unfortunately, it was raining and ice pellets were falling with lots of wind.  But when the plunge began, the rain stopped long enough for us.  Anyway, this may be not what the OP or a lot of people might have in mind with their photography, but it does give people reason to think about being more prepared for all sorts of activities.  For the budget-minded photographer, note that I purchased two nice "Gold Award" 18mp Canon DSLR cameras and two zoom lenses for much less than the price of one 12mp Olympus E-5 camera (about two years ago).  That was a motivation for me to switch.