Thanks for the tip I thinking about what I have been wearing I think you hit the nail on the head and my current wardrobe is probably too formal and stuffy for the current office. I don't have many light and fun work clothes as that was not really accepted in the past, but I think I need to mix it up a bit and wear more sweaters instead of jackets and less ties and maybe add in some lighter colored grey or brown suits. Plus it would be have more clothes I can wear outside of the office, but still look dressy so I might start off by picking up a few after work happy hour blazers.
You don't have to eschew the jacket to achieve informality. Rather, avoid the formal colors (black and dark blue) and opt for lighter colors (beige, light grey, green, etc.), add patterns to decrease formality further, and prefer more rugged materials / textures, e.g., tweed or flannel. There are plenty of examples, to wit: seersucker blazers, hacking jackets.