If you need more than LEDs for indication in your projects, your next option is LED matrices or 7-segments. Adafruit 0.56" 4-Digit 7-Segment Display w/I2C Backpack – Red is a great product to use as indicators in your projects.
7-segments are great, but they have a small problem. You need 14 pins to control a 4-digit-7-segment display and that is a lot of pins to give up. There are driver chips like MAX7219, but that solution needs lots of space and lots of wiring. With Adafruit 0.56" 4-Digit 7-Segment Display w/I2C Backpack – Red, Adafruit solves this boring problem. The 7-segments have I2C backpacks to reduce the number of pins needed to drive the 7-segments to just two.
The driver chip on the matrices does all the needed things for you. It has a built-in clock, so it multiplexes the display. It has constant current dividers for ultra-bright, consistent color and it has 1/16 step display dimming and this is all done via simple I2C interface. The backpacks come with address-selection jumpers so you can connect up to four mini 8x8's or eight 7-segments (or a combination, such as four mini 8x8's and four 7-segments, etc) on a single I2C bus.
A bit of soldering is required to attach the matrix onto the backpack but it is easy to do and only takes about 5 minutes. There is also a detailed tutorial from Adafruit to show how to solder, wire and control the display. There is also a library that can be used with the 8x8 LED matrices and 4-digit 7-segment displays.
The product kit comes with:
Adafruit LED Backpack Learn Page: https://learn.adafruit.com/adafruit-led-backpack
Adafruit LED Backpack Library: https://github.com/adafruit/Adafruit-LED-Backpack-Library
Adafruit Product Page: https://www.adafruit.com/products/878