I would like to see a druid archetype whose wildshape focused on turning into elementals. You could get rid of plant shape and wild shape effects and move the elemental body effects forwards two levels so that the druid could wildshape into a small elemental at level 4 when he normally could first use the beast shape effects in wild shape.
You could further restrict the archetype into taking one of the elemental domains (Air, Fire, etc.).
Personally I think it would make an awesome character, what does everyone else think?