Maybe I was too subtle - but Weatherby isn't know for quality or long term durabiltiy in their shotguns. I'm not saying they're junk either ... I would put them in a group of relatively inexpensive acceptable guns ( SKB, Ruger, etc ) .... but not something you could expect to put 100,000 shells thru with no problems.
Lighter is kind of relative / but remember a gun that is 1 lb lighter - will give you about 15% more recoil for any given load.
Benelli makes a pretty light gun / and if you go with one of their synthetic stocked models, with the comfort tech recoil supression system in it, its a pretty soft shooting gun ( not softer than the gas guns ) - but they're lighter for carrying all day. Benelli Super Sport, as an example, is my prefered semi-auto and even with a 30" barrel it weighs about 7.3 lbs / the 20ga version is about 6.2 lbs - it makes it a very nimble gun for quail, etc...