In general the symbols used for various positions in orbit are too small, often overlapping, and generally hard to distinguish, especially when intercepts are involved. One simple things that I think would help make it more visually appealing and distinguishable as well as add a touch or realism would be to use the "correct" symbols for ascending and descending node. There are even unicode symbols for them - U+206A ☊ and U+206B ☊ (copied and pasted from Wikipedia page on astronomical symbols).
Also, one thing I think was under represented in KSP 1 was celestial longitude and indication of reference direction, typically denoted by symbol for Aries: Symbol ♈︎ (HTML ♈♈ for the symbol without background). \♈