Best options for heat with newborn

First time mom with a 4.5 week old (~8.4lbs, ~54cm).

So far I’ve been using the najell pre-tied wrap. I know it doesn’t get the best reviews but at the start I was intimidated by the wraps and wanted something that went on easily.

Now I feel comfortable and confident in that, so ready to consider other options.

Main concerns with najell are (1) I think on hot days he’s overheating in there and (2) my lower back sometimes aches - I wonder if the pre-tie format makes it less supportive?

Any suggestions on what we should try next? In particular one that is breathable to stop bub from overheating? I was considering a ring sling but see conflicting views on how good it is with newborns? I’ve also considered a structured newborn carrier but I’m less inclined to that unless it’s really good as I already have a carrier I’m hoping to use when he’s bigger.

Thanks!