JRiver's biggest attraction from what I have seen is its functionality, and ease of setup, which is why I chose to purchase it, and stick with it. In terms of improvements, I'll go ahead and beat a dead horse and suggest more plugins, and UI enhancements are much weaker in JRiver than other programs. These two kind of go hand in hand in my opinion because as programs like Kodi attract more developers, the selection of skins only gets bigger. To be more specific, I would like to see a wider range of choices for Theater view layouts. Each user will have his or her own way of interacting with their PC, so I think giving the users more flexibility in what kind of visual, and input environment they choose to run JRiver within could go a long way. Example, all of JRiver Theater view skins are relatively dark, and the user doesn't have the option to remove the darkening overlay feature within theater view easily without breaking many of the aesthetic properties of the program. A dark picture may be fine in a dedicated theater room or on an LCD screen but what about users that have plasma or DLP screens, or those who choose to watch tv in a well lit environment. I have a DLP right next to a sliding glass window in an apartment, and I hate working in dark rooms so when I get on my HTPC, I am forced to deal with a washed out picture. Some users like light, colorful themes, so this should be an option.
Another trend in theaterview is small buttons, and this ties into the whole remote/how a user interacts with their PC concept. It would be nice to see themes with big buttons, and when I say this, I think of how much I like some of the media portal themes so that is the kind of direction I am thinking. Macro support would be nice as well, and it doesn't have to be anything elaborate, just the ability to read PC actions and states, and execute actions based off of that. JRiver has great remote programming options, but it would be nice to see the program execute some actions based on events or state to free up how much work is done with a remote. I could list other things but I don't want to turn this into a two hour feature request. Just my 2 cents.