Pyromed1....
buck converter is a great idea such that you have fewer batteries to manage and these are less dead weight to carry aloft.
With respect to the stick on LED strips please keep in mind, if your MR is made of carbon fiber which is electrically conductive, the sticky side of LED strips may have copper termination points that can potentially short out on the cf....
Load side circuits that short out typically can affect the supply side where the FC etc. are located..... Just one more reason why Multirotors can suddenly crash.