Taking a first look at the interior of the KL07E, it is quite simple and offers the usual layout. Thanks to the fan placement in the front, any airflow generated will provide cooling to the major components above the shroud. That shroud is completely solid with a singular hole in the back. Nowadays, some cases offer dedicated openings for GPU power routing at the center, at the edge away from the motherboard, so this feels a little dated, but will still work fine. On the backside, you can see two grommet covered openings for cable routing as well as a few large hooks for zip ties. While limited in numbers, they are placed at all the important points around the tray, so your cable management should be just fine.
There are three 2.5" drive trays attached to the backside of the motherboard tray. While they look and feel a bit fragile, they do allow for a completely tool-less addition of storage drives. SilverStone has also added two Velcro strips to keep any cables in place behind the motherboard tray, which is certainly nice to see.
Underneath the shroud are three 3.5" drive trays in a cage. In the KL07E, this has been moved over ever so slightly to allow for liquid cooling setups to fit in the front. By doing that SilverStone was able to simplify things and rivet the cage into place, making it immovable when compared to the implementation in the original. The E variant also no longer comes with a cover plate to close off the shroud. That said, it really wasn't necessary in the first place anyway. Above the shroud in the front are two 140 mm fans, which are actually placed on a bracket that may be taken out. This allows you to install a 280 mm liquid-cooling setup with relative ease - simply slide the whole contraption into place and use the thumb screws to secure the bracket.
The PSU bay underneath the shroud offers up to 200 mm of space for power supplies, which turns into a mere 140 mm should you choose to move the hard-drive cage over. Doing so means that you will have to get creative when it comes to picking your power supply. Above that are the seven expansion slots with their locking mechanism outside the chassis. In the very top, you will find the third 140 mm fan; it is set to push air out the back.
Taking a quick peek at the ceiling, you will notice a bit of space between the motherboard and these mounting holes, so we will see if that is sufficient for an AIO. All the cables within the KL07E are of the standard variety and feature black sleeving. While the original utilized USB 3.0 headers for both the Type-C and Type-A ports, this new variant goes for the proper implementation for the Type-C variant.