I recently upgraded my shocks to Monroe.
They have a nifty little app on their website that helps you choose the type of shock for your use/load.
I too wanted something heavier than oem, but not too heavy, since my wife drives the Astro daily with no load.
The new front shocks where much beefier than the oems.
I went with rears that have an external spring around the shock to help with load. I also added Timbrens in the rear, which work great since they only come in to play when heavily loaded. Although you can tell that the rear is stiffer than the front, the ride is now nice, both empty and loaded.