I’m 6’2” 290-300 . WM terra lite with extension was good. I have like a 61 in chest around the shoulders too. 53 in chest excluding shoulders. I actually sold it…..but i may bring it back if my zen bivy doesn’t work out. I will tell you the zen bivy is next level comfort as long as it keeps me warm. Trying it first time this year
I'm a little bigger than you at 6'5". Was about 270lb, currently doing a strength training program that has me closer to 285-290ish. I have the same problem you do. A lot of sleeping bags are simply not wide enough, and length is always a concern too if you want the full hood. My go-to right now is the Wiggys long/wide size bag. That is the biggest that I have found on the market (of affordable USA made gear) and it allows me all the room I need. Quilts are an option too. They have their own set of drawbacks, but they are generally more free moving, and width is a minimal concern since they don't zip up.
I'm tending to lean to the Warbonnet diamondback, but I have not bought one yet. The cost of down has really gotten to be oppressive, basically double 2019 price. If you are ok waiting, Warbonnet often does sales on certain holidays. One of the downsides to a top quilt is if you get drafts they can be tougher to roll up into. Some quilts have included straps to combat this. Really it's not a huge problem though.
As for the Wiggys sleeping bag, it is a synthetic insulation. They don't pack down much, and compared to down it is heavier. My 0F long/wide bag must be around 6-7 pounds. Gear for guys our size is always going to weigh more and take up more room. While a lighter/smaller down top quilt would be nice sometimes, a 6 pound sleeping bag really isn't that bad. It is nice sometimes being able to zip up in a bag and get 360 degree insulation. From what I've seen, the down sleeping bag costs are absolutely insanity.
Nunatak made me a custom bag. I used one of his already in production and then we bounced ideas off each other until we got it right. Bag turned out amazing and I am very happy with it.