There will definitely be more stuff than what's been shown in the Eastern Invasion update, but yeah this patch will be a little light on cosmetics. What we've been trying to focus on is the engine stuff and tech side of things, since there have been quite a few problems.
As for what comes with UE4.25, we'll have native DDOS protection, and more importantly whenever epic updates UE4 they tent to not only fix a ton of things, but make it easier to work on actually making games. This means that going forwards
On the tech side of things, pretty much every weekly meeting notes (you've all probably gotten bored of it) say something about optimization. Optimization rarely means that we can fix some issue and everyone gets 5 more fps, instead, it's a ton of little changes that end up resulting in like a quarter of an fps gain in performance. While that sounds lame, if you do enough of those you actually start to see some big improvements. Aside from DDOS protection, there's been a bit of network stuff we're doing behind the scenes that should help with server problems. This is both game related netcode stuff, as well as annoying the hell out of our server providers to investigate potential issues on their end.
Overall though, our idea is that content is great; new content definitely brings new players into the game and entice existing players to return - the issue that we've seen, though is that they don't stick around. We have been working on fixing the issues that mess with retention, so that way the big content updates planned for the future have a good 'foundation' to build upon.
p.s. cloaks aren't in the cards at the moment - we've experimented with the idea and there are a few potential ways to add them, but they're not really like other armor pieces - we'd need to do some backend coding stuff to get em working, and everyone's tied up with the engine upgrade.