It's probably just me, but I would definitely use Stealth Rock AND Roar on Hippowdon. The standard physical walling set doesn't have that much power, and Ice Fang is only situationally usefull. It can't take out Gliscor thanks to Roost, and the 95 Base Acc is just begging Chompy to Hax veil it. Stone Edge has PP issues and most of the things you'll use it on get hit for 25% from SR anyway.
If you can, make sure to mention that better leads often have multiple good lead attributes.
Gengar for instance combines status with sweeping. Bronzong can status and use entry hazards.
Most of your Bulky leads are in fact usually shufflers as well. Being Bulky alone doesn't help a lead much. Blissey is bulky but it's a horrible lead. Registeel is also bulky and has status, but it has questionable lead qualities. Dusknoir is bulky too, but isn't a great lead either. In fact, most of your walls should not be leads because you should save them for later and suprise your opponents.
Bronzong is basically the exception to this rule because it has Entry Hazards and Status going for it (and a bajillion resistances).
Scarf'd Trace Gardevoir has worked well as a lead for me. Essentially it can mimic Intimidate leads and punish Pursuit users with a shaky (but deadly) Focus Blast. It also has Hypnosis so it can use status. It might not deserve in-depth, but its been quite effective.