First Spirit Run Completed. Low Heart Yield. Need Advice

[Toph]

Hey guys. Just completed my first spirit run and I'm a bit caught off guard by the low yield of hearts. Hoping someone can chime in and give me some input.

Now I understand I'm not exactly running a big operation here, but I still anticipated more than I ended up with.
I'm using a 3 gallon reflux still. All runs had copper mesh in the column. I'm running a recirculating system with a bilge pump for the condenser. Mash was a sweet feed mash, corn oats barley with some molasses. 4 inches of grain in the bucket, 5 lbs sugar, boiled a couple gallons of distilled water, let sugar dissolve, and once it cooled just below 90 degrees, (and after adding 2 more gallons of water) added 2 packs active dry yeast. Let it ferment for about 6 days till airlock bubbles almost stopped, racked and let settle a couple days, racked again. One stripping run yielded just over a gallon.

After a few stripping runs I did a spirit run of about a gallon and a half. Ran it slow and collected in 8oz jars. Jar 1 is about 170 proof. By jar 7 it ran low at about 40 proof. Jar 4 seems to be my only heart. And is 140 proof. Jar 3 burns the lips a bit and seems more heads than hearts. Jar 5 and on is clearly tails. I guess if I collected 4oz at a time I may be able to squeeze a little more heart out. But 4 gallons of wash, 1.5 gallons of stripping runs, and a total yield of 8oz usable shine seems slim.

If you see anything I did wrong here, or maybe find that my expectations were off, I'd love some input. Feel free to ask any questions I didn't outline.

Thanks guys, I appreciate the community and all I've learned here so far!