The best product I used for sealing cuts on tires is a wetsuit repair product named Aquaseal. It is really tough. Hand cycle and wheel chair racers told me about it. They actually coat their gloves with Aquaseal to prevent gloves from wearing out. Far superior to Shoe Goo which I have also used. Then they discovered it was great for repairing cuts. I use it all the time.
The cross brakes you see are all right. The cable from the regular brakes runs through these brake levers so you can use either brake. True cross racers avoid them as unnecessary. When you're going hard, which is all of the time in a cross race, you're down in your hooks.
Jim Cushing-murray
Del Mar CA