I like several of the Strymons. They have that combination of simple aesthetic and a cool color that looks harmonious with the knobs chosen. They never have an aesthetic that seems like it tries too hard or sacrifices clear labeling for visuals.
Analog Alien Fuzzbubble-45
Earthquaker Devices Space Spiral Modulated Delay, have the limited edition commemorative 2017 Carlton Music 50th anniversary "Jaco" the dog artwork (almost all EQD pedals have great artwork including some limited edition releases)
Walrus Audio Slo Multi Texture Reverb, have the 1st anniversary limited edition red 2020 (same goes for them as well)
Alexander Pedals Space Race Reverb (Rainbow Saturn V limited edition sparkle 2021)
Matthews Effects Cosmonaut v2
Shift-Line Astronaut Reverb v1
Electro-Harmonix Small Stone Nano v2 (love the psychedelic swirls of the 60s look)
MXR Phase 90 (just love the simple iconic orange color)
BOSS Waza Delay DM-2W (the same goes for this one)
Ibanez Tube Screamer TS9 (and for this one)
Catalinbread Adineko. For a company that shows up in the ugliest category a lot, they deserve a lot of credit for making the Adineko have a meaningful graphic and clever aesthetic. The controls have slightly odd names until you learn about how an oil can delay works and then it all makes sense. Even the slightly worn metal of the enclosure is a nice touch. This is decent to very good graphic design.
I always thought that Chase Bliss Audio makes nice looking pedals. The discontinued Ayahuaska is an exceptionally nice looking pedal, but all of their pedals have a nice clean aesthetic as illustrated by the Mood.