Most 28mm artillery crews are dress in summer uniforms.
Being a gunner is rather a active job & in summer months can get very hot & demanding for the gun crews.
With this been said I think it would be a good idea for a manufacture of 28mm minis to produce field gun crews in rolled up shirt sleeves or even, dare I say it... topless!
I would also suggest two sets. The first wearing puttees & the second set wearing jack boots. (or maybe one box with both).
If WHA ever got round to making such a range I would also suggest that these figures could be probuced headless. Heads could be used from the WGA infantry ranges.