77c isn't a lot really. Just recently exploring systems I've easily got up to just 500+ going around in circles looking for moving planets in the system... for me very relaxing and fun, for other - boring as sh1t.
Some systems have planets several hundred thousand km away from the star. (I've heard some have over 1 million in distance but never seen one yet). Just think how far our own pluto is from the sun (about 38.2 AU)
1 AU = 149,597,871 kilometers
I suggest when the game goes live you head to our very own SOL system and fly from the sun to earth, then you will understand the sheer size of the galaxy more.

If you don't know 1AU is the distance from earth to our sun.