I think I'm a reasonable looking 42 and I'm not fat, 5'7 and size 10 in a full skirt, 12 in a fitted skirt, but I do carry my weight round my thighs, so in skinny jeans I would need a 14 which would then be far to big round the waist and not at all flattering.
I've tried straight leg which look frumpy to me and bootleg seem very dated, so what else is there? I'd pay a decent amount of money for a good pair.