Silios,
First off, welcome to the Forum! Hope you join us often as its a great resource.
As to your 8300 darks, I have two 8300 CCDs, an STF8300 and an STT8300. Your master looks very similar to mine, though I typically shoot lights with these CCDs at 300 seconds or less (I use them with a very fast f3.3 astrograph). As such, you show more hot pixels than I do, but that is to be expected since I run at colder temps and do not shoot my darks for longer than 300 seconds.
The key is what those darks do when you process your lights. If they are cleaning up the images you are all set. But if you are scaling, be sure to include a master bias frame and to check the calibrate and optimize buttons in the image calibration tool. Dithering is also important, if you can manage it. My first two steps in PI are to calibrate the lights, then run them through CosmeticCorrection using a sigma setting of between 2.5 and 3 for both high and low. At that point you should have nice clean subs ready for testing with blink and SubFrameSelector.
If you are scaling and not setting up the calibration tool correctly, that could be what's causing your issues since you will be way out of line between your master dark and your lights and that leads to problems with hot pixels and cold pixels. You can avoid this issue entirely if you shoot darks for the same iteration time as your light frames. in that case you don't need the bias or to check any boxes in the calibration tool.
Hope that helps but if not report back and we can try something else.
Best,
Jim