diff --git a/README.md b/README.md
index 55a032d..0b20c89 100644
--- a/README.md
+++ b/README.md
@@ -7,12 +7,19 @@ Features:
 * Two MOSFET drivers fans
 * One big MOSFET driver for a hotend heater
 * Thermistor input
-* Servo connector
+* One servo
+* One endstop
 
 
-It should be fed from the mainboard with 12-24V, 3.3V or 5V, GND, UART RX and UART TX. 
+It should be fed from the mainboard with 12-24V, 5V, GND, UART RX and UART TX. 
 
 Possible issues:
 * Is the cooling for the TMC2209 adequate?
 * How well will the UART cmos/ttl level survive? Noise?
 * Does it work
+
+Alternative design options: 
+* Use an ARM instead? STM32F030
+* Create a local 5V/3.3V instead? Switch regulator + LDO. Only the servo needs 5V
+* USB-c would be neat, it could provide all the power and signalling needed
+