Trap vs. Skeet
The only time I found the 20 inadequate was at trap where the extra shot of a 12 guage makes a significant difference in my score. On the skeet range I do just as well or better with 20 and have hunted pheasant with 20 though I like 3" shells for that. I have seen real experts clean up on the skeet range with 1/2 oz 410 loads. Given your wife is not a dainty gal, I'd say the right 20 will do everything your wife wants and will be OK for informal trap shooting where score is not a big deal. Since it sounds like she wants to shoot a lot you would have to reload 410 for cost to be competitive with the bigger guages. Last I checked 410 is about $10/25 and 12/20s are about $5. There is alos a lot better selection of 20s than 410s.
The only time I found the 20 inadequate was at trap where the extra shot of a 12 guage makes a significant difference in my score. On the skeet range I do just as well or better with 20 and have hunted pheasant with 20 though I like 3" shells for that. I have seen real experts clean up on the skeet range with 1/2 oz 410 loads. Given your wife is not a dainty gal, I'd say the right 20 will do everything your wife wants and will be OK for informal trap shooting where score is not a big deal. Since it sounds like she wants to shoot a lot you would have to reload 410 for cost to be competitive with the bigger guages. Last I checked 410 is about $10/25 and 12/20s are about $5. There is alos a lot better selection of 20s than 410s.