I've searched far and wide about this, so I'll ask here. I came across the teensy 3.6 at the local microcenter (it has the MicroSD already on it, plus a faster processor). I have the prop on order from sparkfun, but I imagine there are changes in regards to the SDcard script. I'm mostly new to programming.
It comes down to two things here:
What changes will I have to make in the code for the SD, and where can I figure out how to make this thing work with a single 3.2-3.5V 1A XP-E cree LED? (I have a white LED I can squeeze in for the clash effect if needed, same voltage with 0.7A)
Short answer: I don't know.
Much longer answer: I don't think you have to change much, as the SD card interface is very simple. Teensy 3.6 has some new features that lets you access the SD card faster, but I don't know what you would need to do to use those features. I have a Teensy 3.6 sitting on my desk at home, but I have not tried to use it yet.
One thing to watch out for though: The Teensy 3.6 has the Audio Out (A14) in a different position than the Teensy 3.2, so you'll need to make that connection with a wire instead of a pin. Shouldn't be a big deal, but could be very confusing if you didn't know about it. (The rest of the pins near the short side of the prop shield are not required, so I don't think you have to worry about those.)
A FET and a resstor per LED is all you need for the LEDs.
For the 1A LED, the resistor should eat 0.2 volts, which at 1A means you need 0.2 ohms. The means the resistor will emit 0.2 watts of heat.
For the 0.7A led, you'd want a 0.14 ohm resistor, which will emit 0.1 watts of heat.
I assume you've looked at the circuit diagram: Teensy Saber Electronics
PS: This the intended place to ask questions, feel free to ask more!