sirgumby is the biggest and purple. uranus is probably next, colored green. I'm right in between the two, and then there's pretty much nothing but 2-3 system players all the way to the core.
Found you. I was looking around for single planet empires for ages, you're a lot further than I thought you would be for a "couple" of days - your home planet says 11 days
(I'm presuming home planets grow by 1 level a day).
Your nearest neighbour is Fodder. If you go out two rings and then counter clockwise four segments, he's the yellow one. Near him is Silverfire (KingDante, orange) and Squishymaster (grey-blue).
If you go inwards 2 rings and clockwise 7 segments you'll find Adriddae (vistuvis, orange).