Definitely.

First of all, I paid a lot more for the lumber in June/July than I would if it were happening now. Lumber prices came down a lot from 2021 into 2022, but they're continuing to drop. I was paying about $6 per 2x4 and $25 for 7/16 OSB, and I think that's more like $4 and $15 now.

Secondly, I think a little bit of cost could be saved by buying in bulk. I was kind of figuring each step as I went, so I really only bought things one step at a time. If were to make a list of everything beforehand and order it at once, I think there'd be a discount there.

As for making design changes:

I think the easiest first step would be simplifying the framing. I could have built the walls with studs at 24" instead of 16", used a single top plate on the walls, and put the rafters directly on top of studs. I probably didn't need to use two king studs on each side of the double door, I probably didn't need a solid sandwich header above the door and window on the load bearing walls. Making all those changes would probably cut the framing step costs by 25-30%, and I imagine it would still be plenty strong for the size that it is.

I chose to sheath the walls with OSB, then use a vapor barrier, then put on siding, but a person could also just put the siding directly onto the studs, especially if they weren't planning on heating or cooling it. I think most people would consider that good enough for a shed.

On the subject of choosing not to heat or cool the shed -- if a person decided up front they didn't were never going to heat it, that would save money on roof vents and the ice and water shield on the roof.

Removing the windows would save a lot of cost -- first, there's the cost of the windows themselves, but there's also costs from extra framing, extra trim, all the flashing tape, etc.

The double door could be simplified a lot. A 2x4 box with just a piece of siding on it would probably be good enough. Maybe one cross support in the center, and a turnbuckle diagonally to prevent sagging. Plus those hinges I used cost about $30 each, and I needed 6 of them. I could have just used regular shed door hinges -- I think those cost closer to $30 for a complete set.

One relatively small thing that would have saved me money is nails vs screws -- I chose to do all the framing and sheathing and everything using #9 "GRK Multipurpose Screws". Those are special screws that are approved for use in framing, and cost like 15 cents a pop as a result. I wanted to do screws because it gave me the chance to take things apart and redo things. All the pros use nails, which are cheaper and probably better suited to framing anyway. Heck, I probably could have bought a framing nailer and used framing nails and still ended up paying less than how much I paid for screws.

There are probably other things I'm not thinking of, but those are the things that spring to mind.