My daughter, age 10, finds it easy to re-enter her packraft by reaching across it and grabbing a webbing strap I install around the perimeter of the raft. It is just a 1/2″ piece of nylon webbing run through tie-down attachment points.
Having webbing around the bow, and another around the stern is sufficient too. I run it from 2R to 1R to 1L to 2L. and another strap from 4R to 5R to 5L to 4L. Having a thigh strap completes the grab point options. And I find the thigh strap the most likely point to grab onto if thrashed and blown out of the raft in a substantial hole or hydraulic.
To save weight, a strip of 1000D fabric is even better than the webbing. It is plenty strong (420 is probably fine too, but I haven’t tried it yet) light, and doesn’t pick up water.
I have heard plenty of stories of rafters who got tossed, only to have their feather light raft blow away faster than they can swim! So having something to grab onto as one falls out can save a long swim!