Good job on the weight loss and the strength gains. My grip strength limits me, too. I use straps for heavy deads. My .02 on the LBM issue: as long as you continue to build strength, I wouldn't worry too much about losing lean mass at your current weight. You can always add on a bit of lean mass in a small, controlled, clean bulk later on if you decide you'd like to.

And curling the 15s is pretty damned cool!