<font color=blue>"two 3/8" grab hooks at the two top corners of the bucket with a 3/8" slip hook in the middle"</font color=blue>
The only problem I see with that (and it's a big one) is that unless you're always hooked perfectly evenly to both those end hooks, you run a great risk of really torquing your bucket and loader arms from effectively pulling with just one hook at a severe angle to the strength of your loader. Remember, with anything other than a perfectly straight pull or lift, one hook is taking the load because the chain is locked into the hook.
I'm going with hooks on the bucket at the loader arm attachment points instead of the ends. It just makes more sense to me to have my areas of strength aligned. I'm not saying my way is right, mind you. I'm only offering this as an alternative for you to consider. I hope this helps.