I have ideas for several stuff:
A new system including: Kalneo as the sun, a kerbin-like planet: Sintina with Ope as the moon, normal planets: Dlopo with Asto as a moon, Wolew with Qeo aka its moon, Non-atmospheric planets: Neo, Ezu and Kop, a gas GIANT: Junox along with its moons: Dasgo (which was actually a planet that got captured by Junox), Mino, Gver and Bompo. Junox will also have Rings!
New parts: New real life cockpits, A whole new rocket size: mk4 including a 7 seater pod, fuel tanks, decouplers and engines: 2 vacuum ones, 1 first stage engine and a srb. Oh and lets don't forget the Solid fuel tanks on all sizes.
New feature: Painting parts, so I can finally make jacksepticeye's logo.
If only squad could make a 1.13 update, wow they would like to see this!