I don't often cut single layer material over 1/2" (with the exception of compound cutting). Even when I'm stack cutting, I try to keep the stacks a little thinner than most, maybe 1/2" - 5/8". I just find those thicknesses much more enjoyable to cut than thicker stock.
I routinely cut 1/2" hardwoods with a #1 FDUR (Flying Dutchman Ultra Reverse) blade, with no problems. If the pattern is relatively simple, I might step up to a #3 FDUR. The going may be slower than some would prefer, but as a hobbyist, I usually don't have any need to cut fast. If I were cutting 3/4" white oak, I would probably reach for a #5 FDUR, if the pattern has some detail and tight turns. If the pattern is simple, maybe go up to a #7.