Redesign private message boxes

[eveneme]

The private messaging box should be redesigned to resemble more of an email or private messaging interface, examples of which I'm providing below. Currently, it looks more like a thread list on a forum, which, in my opinion, doesn't look very appealing.

Examples:

[eveneme]

Examples V2:

[eveneme]

Examples V3:

[eveneme]

Private messages should have a design similar to the inbox, so that they are more associated with private messages, as currently they look like a list of threads. I'm sending examples below.