I agree that without some kind of goal in mind, focusing on analytics isn't useful.

Golden Cheetah is a lot to bite off. I do have it, but I don't pretend that I'm getting a lot out of it.
I find Training Peaks useful, but mostly for creating/executing/monitoring a training plan, which you're not doing. It doesn't barrage you with data, although a lot is in there if you pop the hood. One nice feature it has is that it will estimate TSS based on heart rate, which is something intervals.icu can't do. If you're getting a power meter, that's moot.
Just to muddy the waters, you can also look at Cycling Analytics, which seems pretty slick. I haven't actually used it.