It actually took me a while to get a controller but when I finally took the plunge in late 2017 I grew to love it. There’s just so many things a controller (or CDJ) lets you do now that software’s in control.
I wouldn’t pretend to have mastered all of them but as someone who mixed vinyl for more than twenty years beforehand there’s three features I’d definitely recommend to anyone contemplating going digital.
P.S. I’ve focused on the digital tools themselves rather than the obvious benefits of the form factor.
Loops
The loop function (as the name suggests) allows you to pick a set of bars to repeatedly loop in a track.

On a vinyl record you’re fundamentally limited to what’s been pressed. If there’s not much of a run in to mix with or the track ends abruptly you’re kind of stuck.
Being able to loop a section of the track, at the beginning and automatically loop a section at the end means you’ve been given the gift of time, or can afford be a bit more creative if you’re stuck with just a radio edit of something.
Cue points
Part of the art of DJing from vinyl (unless it’s DVS) is learning to spot the significant points in the track – e.g. a darker ring indicating a breakdown or vocal section. As a technique it’s not foolproof and requires a very good memory.
Whilst a digital waveform can be read to a degree on a screen I’ve always found it even harder to read than vinyl.

Hot Cues though allow you mark out the track and even give them a name so you can remember why the point is significant. Both Rekordbox and Serato DJ have this feature – they work and export in slightly different ways but the idea is the same.
I find this useful for plotting things like when the beats and melody come in and out, or when the main vocal comes in (useful for radio mic work). It only takes a few minutes to set up too.
Key analysis
There’s always those tracks that just always seem to blend together well, for example a particular accapella that went well over an instrumental or a dub. In my experience discovering a good match was largely down to chance. Also if you have a great track with no beats at the start or end, you can end up clashing with whatever’s coming next if they don’t work harmonically.
Thanks to the power of software like Rekordbox and Serato DJ we now have more chance of a nice harmonic mix since they will analyse your digital files, and tell you what key the tracks are in. If you have two tracks with matching keys, there’s a good chance they’ll blend nicely.

Both Serato and Rekordbox can specify the key according to the Camelot Wheel which is an easy way of working out which keys are harmonically compatible.
Next time you are stuck with no beats to play with at the start or end of a track you’ve got the option of finding other tracks to blend together with it.