Thanks to KeepCalmAndGameOn for some cool new review/gameplay videos. I'd suggest his second video as a great example of early gameplay.
https://youtu.be/k3VWM8yhzlU
The newest game update adds 3 new Chrono Mutator skills, to increase your ammo, cheapen the ElectroGun, and boost the Chrono Mutator points you get from killing shuggoids and guardians. This should help hardcore players aiming to defeat the ultimate sector, 9999.
And speaking of 9999, it has now been officially beaten! The Hidden Object Guru defeated it on medium density (and in VR, no less!) while I have completed it at high density playing on desktop. It took me a lot of Chrono Mutator respawns to get there, and I'm guessing my time won't be too hard to beat. You can see the videos below.
Note that 9999 is quite dark since it has the Blackout challenge, and play style is much more cautious than usual because the sector is full of guided missile firing thanatoids who can take you out with one shot!
https://youtu.be/me8_qGF_w68
https://youtu.be/-_VNVlU9eNQ