I'm all about waist surrender in heat. Can barely tolerate even my lightweight jeans.
Yes, I'm aware I look sloppier --- especially since I favour cottons and linens that love to wrinkle, and don't like very fitted garments and structured collars etc in summer --- but for me it will always be comfort over fashion. I'd *like* to learn to add fashion to comfort, but the other way around just doesn't do it for me.
Interestingly, as of yesterday, I've started using Suz's idea of winter-weight shirts as jackets. It looks less ludicrous to carry one in the heat, and adding a scarf makes Arctic Office just about bearably cold.
Another odd strategy: I like my hair is what goes structured or 'fitted' (pulled back) in summer, while I let it be wild and waving (whether long or super short) in winter. Okay, not much choice about the latter --- it's adamant! In fact, just got my summer cut this afternoon -- less layering, just long enough to tie back.