What about the new ergo performance. It's made of cool mesh so will suit a hotter climate although you will be using an infant insert from newborn so that could be hotter. It's also more slimline and better fitting and will have all the known benefits and comforts of the ergo - I have a sport here in QLD and that would be my preference above an original ergo. Or I'm thinking if the prospect of wearing a ssc with an insert in summe is too much maybe a ring sling made of a light fabric like the the breeze baby..will double up and take you in the water too. I used a ring sling for four months then Ergo up till now, but regardless of what you have..its gonna be hot! Breastfeeding on the go with an insert will be quite hard but you should be able to do it better in a ring sling as you can adjust easily back and forth and with correct positioning you should have a nice close feel so you can go about your chasing a toddler feeling safe enough