I don't have chucks and they won't let me deadlift barefoot. I do have these loafer type shoes that are quite flat (80% as flat as chucks) and I was using them. I honestly think I just like the WL shoes more. I can't say why. I just feel stronger with them. I've deadlifted barefoot in the past. From what I remember I like WL deads more then those too.
Thanks for the advice. When you say back, you mean away from the bar not down towards ground right?
What I mean is basicly the same as the people saying "take the slack out of the bar". You're in pretty good position at the beginning of the first rep, you're kinda doing it there. You couldn't hold it and weight went forward a little and your hips shot up first though. The rest of the reps you didn't lose position, but the bar was a little too far ahead of you and you didn't do that little sitback and taking the slack out that you did in the first rep. That sitback and tightening is what I'm talking about.
When you sat back and into position as you did on the first rep, you stayed there for a little too long, losing a little bit of the focus and tightness and then hips shot up when you started the pull. What I suggest is resetting and sitting back like you did on the first rep, each rep, to get better at it. Also, when you sit back into position, use that momentum of coming back to feel the weight being pulled into your hammies and glutes, be tight, and then pull. Don't wait too long between getting into position and pulling. Btw, this is all seperate from whatever hip height you prefer to pull from.
Anyway, it's always hard to give any advice over the internet besides the very basic things. The reason is, how the deadlift works for you isn't necessarily the same as for me. There's how it looks, how the cues you're given effects you specificly and how it FEELS to you. While some things can be considered generally good advice, like bracing, getting into good position, tight lats and such, many things simply differ slightly from person to person. Just look at variations in the way many strong people deadlift.
You made a good point. It's about being sensible, but it's also about doing what works for YOU. Keep losing weight, stay healthy and have fun.
PS, rethink buying good, firm, flat shoes. It might surprise you.