When I have fished the Waal I have used the stick float and pin.
Much of the Waal like many Dutch rivers has a boulder bank which can be a bit difficult and un-comfortable, but out a rod length or so the bottom is sand and fairly flat.
Main species were Brasem (Bream), Voorn (Roach) and Vinde (Natural coloured Orfe) with some other Ide species, Barbel are present in some sections, Dace and Chub are virtually non-existent.
You don’t have to fish a heavy feeder miles out to catch, most fish will come to regular feeding on the inside, in fact you might find you catch more.
Of course if the flow is super strong you may have little option than to fish a big feeder, but if the flow is fairly steady, you might be amazed at how you get them queuing up on the inside.
PM me if you want more info.
Tight lines