Why to carry a space/thermal blanket? Do you use it for something else than just keeping you warm? I would guess that your normal riding gear keeps you warm enough. I might take instead an eye wash bottle which has an ergonomic eye cup for washing. Getting dirt to your eyes is quite common even if you wear proper safety gear. Just as you stated below, if I need to cut/remove equipment a pair of trauma shears are ideal. I have a benchmade tactical stapcutter that I keep with me as it is smaller and will go through just about anytype of riding gear. But you have to be careful because it will go through a person easily too. Once the clothing is removed I may not be able to maintain body temp and a thermal blanket is ideal for that. And even if the individual was thermal regulating just fine they can decompensate or go into shock and drastically reduce body temps.
I would also substitute the Leatherman for proper scissors which actually can cut though riding gear if needed. refer above, good idea!
What would you carry for cooling burns, besides the Camelbak? Is cold spray or cold gel worth carrying? So a lot of these over the counter burn agents rely on topical local anesthetics and generally only work for a short time. The goal with a burn is to clean as much as possible (with sterile or an antimicrobial agent) and then cover with a good dressing while out and about until further care can be provided if necessary. So if a burn agent makes this more tolerable for the initial scrub down to remove debri or what ever that is a good idea but its effects will wear off shortly. Give them 800mg of ibuprofen to help with pain/inflamation, keep it clean and get to proper treatment. Burns are no fun!