Nick,
you have some good ideas. The chair is a great concept, I am sure if you refine the aesthetic and can drive down costs this will be a great success. Especially for use cases like on outdoor terraces at bars, restaurants, ice cream salons, waiting rooms etc. when more people are joining than there are chairs. Consider gas-assisted IM or rotational molding.
Regarding your presentation, you build a lot of fluff around your projects and don’t tell much of a story. With elegantly composing text and the necessary images that communicate, you can build a more cohesive story. I’m not into the way of presenting projects like a rolled out powerpoint, and your way of sketching is different with each project. You can work on that and build your own style. I speak from a background in the mobility sector and your sketches and 3D work is just up to par, it’s not very good though. Search for something that stands out. Refine your sketches and use white more sparingly. Use pencil instead of ballpoint to sketch underlays for ink drawings. Some of the digital sketches are ok. Also simplify your typography - when opening a project page there are 5 different typographic styles on the screen. Small caps works only with small caps fonts, and even then only with a few of them it actually works well.
Some of the helmet sketches are pretty good, make sure you gain feedback from your user group, especially with ski helmets this is often a major factor in the purchase decision.
Overall it’s a decent portfolio - you can mainly improve on storytelling and refining your design skills.