Kernel will likely remain pretty static. Important updates will be made, but nothing fancy or new.
Security will always get updated.
Software will be hit or miss. Important bug fixes will make it, new features most likely won't, but it's up to the developer.
If your on a server stick to LTS, if your at home I recommend just updating to the latest version. Though you have to make the call. LTS versions are more tested, and stable, but only in the programmatic sense.
For example. Lets say you have tEdit (a fake text editor) in LTS, in current (non-lts) it gained the ability to copy and paste. This update also caused a bug where you can't tab.
LTS probably would not get that update as no one is really using tEdit, and it doesn't effect performance. Though some one out there may really like tEdit and may publish personal repositories that will let you install. This means current would get a tEdit that can copy and paste but not tab (till they fix the bug), and LTS would not be effected byt the tab bug, but would also not be able to copy and paste.
The basic idea is "better the devil you know" and it 100% true for business/server environments.
Now lets say libKeyboard (again fake) gets an update that allows you to not crash when pressing caps lock. That would end up in both LTS and Current because it effects everyone and is down right important.