I don't think I've ever heard, or at least noticed, a coach recommend to start using hook grip so early. I imagine that would help somewhat with the discomfort, even if it's just getting used to it gradually. If someone is utilizing an alternate grip, would you recommend gripping the same each session or alternating which hand you turn out? Thanks!
I would recommend avoiding mixed grip at all costs. It can lead to ripped biceps which requires surgery to get fixed. Just google 'deadlift ripped bicep'. Hook grip and straps are the only safe options if you can't hold the bar with conventional grip anymore.
Any advice for making your back tighter? I use a belt, I tighten my upper back and lower back as much as I possibly can, but I just can'ttttt get my lower back tight enough. There's always a slight bulge when I start pulling heavier weights (from like 140kg when my max is 165 for 3x5)
When do you take your breath? Try setting your back first and then a big breath, brace, and then grab the bar, set yourself up(Quickly, because you need to hold your brace), and then pull. This is what I do right now.