Exterior insulation on a smaller home in Climate Zone 5 – GreenBuildingAdvisor

Currently in the extremely early planning stages of building a new house on a city plot in southeastern Wisconsin. Most of the building science information I’ve absorbed is from Matt Risinger (who I know specializes in southern climates rather than northern, so some of his stuff isn’t necessarily applicable to my area) and Asiri Designs, with several threads on this site also being very useful.

The plan is for a single story house with a conditioned attic and no basement, keeping an addition as a possibility down the road. As of yet, I do not have a floor plan. I’ve mainly been talking with my dad for ideas on heating and insulation, his recommendation was to just do regular 2×4 framing, no exterior insulation, and closed cell spray foam it. Neither of us are super into green building practices, so I’m fine with spray foam, but as a comparison I’d like to get feedback on the idea I had for a wall assembly.

From outside to inside, cladding (have not decided on what exactly would be used), air gap for drying, staggered rockwool comfortboard, zip sheathing, staggered 2×4 on 2×8 framing, dense pack cellulose, intello with a service gap, then drywall.

Have I overthought this wall assembly or would this be a reasonable assembly performance-wise? Would staggering on a 2×6 be a significant performance difference? Is the staggered exterior insulation overkill for a smaller building?

Winters can commonly reach -20f on the coldest days, but summers can be very hot and humid at times (usually highs are in the upper 80s, but can spike to mid-90s). I’d have to check actual average temps and humidity for more exact information.