Sounds like your 036 needs a tune up or a piston or something. They are one of the bestsaws ever built in their cc class.
For 15 cords I’d probably put a 30 with skip on the 036 if you can get it running strong. Not ideal at all but will work for occasional use when you just need inches.
A 660 would be nice but I doubt you can justify one for 15 cords. You can get a used husky pretty cheap though if you want a big one. I have a 288 that’s a beast for the money. IMO there’s several reasons husky is cheaper than stihl and doesn’t have near the resale. Good saws, but appropriately priced under a stihl. In your situation I’d be tempted to take advantage of that poor resale.
I don't deny that Stihl makes a Good saw, but I have owned Huskies for 28 years, and have Never regretted my choice. They have been well made Reliable saws, and that original 266XP is still Earning it's keep
I have yet to see anything to make me even consider a Stihl being any Better saw than a Husky of the Same Class
If Huskies are "Appropriately Priced", then Stihls must be "INappropriately Priced"
I don't know what resale value is like for either in Texas, but here on the West Coast, where we have BIG Trees, Huskies hold their value just Fine
If you are Happy Over Paying for a Stihl, by all means feel free to continue doing so. Personally my "Appropriately Priced" saws have served me well for over a Quarter of a Century, and continue to feed the stove heating our home very nicely