We have been in some of the same quandary. The boat, also about 20,000 lbs. (37 feet), came with a 35 lb. CQR. We bought a 35 lb. Manson and have thought about selling the CQR and replacing it with a 45 lb. Manson, but I worried about hauling that out by hand.
I found a used manual windlass...
...and added it to the boat and also a second bow roller and the windlass piviots side to side to work with either anchor (2 rode lockers also) so could go to the 44-45 lb. anchor now but have decided that if things get really bad we would just put the Manson and the CQR down. If we ever get back on the water with the boat we will see how this approach works and go from there.
We had also considered the fortress option and have a FX-11 for the Mac but have never used it. I think the fortress is probably a great anchor in the right bottom, but I trust the Manson about everywhere and even thought the CQR doesn't have great test results compared to newer styles it has worked for a lot of cruisers for a long time.
I think if the combination of the Manson (in your case the Delta) and the CQR down at the same time wouldn't hold then you are in some really bad stuff,
Sum
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