For me, it's a good idea to have 2 card slots when doing a wedding in case one card fails. The Tamron lenses are amazing. I have used the canon equivalent and I can't see any noticeable difference myself. I know if you look into each pixel you will see a difference but I'm not looking to do that.
Moving from the 50mm1.8 to a 1.4 is definitely worth it. I however wouldn't move to mirrorless myself yet. If you have a mirrorless camera, you need about 5 batteries for a days work compared to one battery on canon.
Thanks for the comment, it's good to get a conversation going!
I've never looked at the mirrorless that way, I mean regarding the batteries. It's not that I want a mirrorless but I want a smaller camera. Also de Fuji ones look very cool, as well the Olympus, like the early 80s look of my Canon AE-1 (which does have a 50mm f/1.4 btw). I'm not a pro, I don't make a living out this so I can experiment a little without not being able to make rent.
I own a t3i I bought new and at a really good price a couple of years ago and at work we updated to an 80D, we use both for video most of the time.