In a proper streetcar suburb there should be a supermarket at the tram stop. Also daycare and small primary school, a hair stylist, a GP office, and a restaurant/takeout. Parcel pickup. You only take the tram if you need to go somewhere that has a larger catchment area than a tram stop and especially the supermarket and takeout should be directly at the tram stop so that commuters can grab something on their way home, the rest can be a bit more distributed. One tram stop might have a clothing store, another a shoe store.

Have plenty of bike parking that doubles the radius for the catchment area. housing density should gradually fall off from the tram stop outwards, you can e.g. have a couple of 8-storey blocks around the tram stops with a quasi-urban feel surrounded by 3-5 storeys interspersed with football pitches and greenery and playgrounds, then terraced homes, then finally single-family homes. As to street design: Plenty of cul-de-sacs and traffic calming, make sure that the cul-de-sacs are only for cars, bikes can continue on (you don't need separate bike infrastructure in traffic-calmed areas), also plenty of small paths cutting through everything so kids can visit friends living away 100m without you having to get on a highway first.