The keel hardware on the H-34 is really stout; I've not heard of problems. The attachment to the hull is especially robust with flange "ears" that are wider than the top of the fin. The boat can develop a bit of a "smile" (small gap between keel and hull) especially the forward part. My boat had one after striking an underwater pipe/piling. At the next haulout, the keelbolts were retorqued (with weight of boat on the keel) and I have not had a recurrence in the +25 years since. Note that if there is a slow water leak around any of the bolts, be cautious about possible corrosion on the studs due to crevice corrosion.. Of possible concern would be the shroud anchor points inside the boat. Carefully inspect the bottom of the big tie rods inside the side storage cubbies..
Forestay: If the forestay fails, the mast may well fail, but it depends on the design of the furler bottom attachment. The B& R rig is not different from other rigs in that regard.. The Backstay is a different story. The later Hunters had a "backstay-less" rig but they were designed that way. The H-34 spreaders are shorter and not swept back as much so that rig would have a tougher time remaining stable without a backstay.. If your topping lift is stout enough and the main is sheeted in close to centerline, there is a chance that the rig will not fall.