Great that you can try out your 1280db on your desktop.
Don't worry, you're not crazy for liking your pc speakers.
Remember, you're already accustomed to the sound of your brighter speakers. AND, you likely watch your TV, and listen to the 1280db, at a much further distance. When you have them on your desk, the bass is going to hit you harder because they're much nearer. Next, they're up against the back wall, so there's boundary gain and the bass is essentially increased from the wall reflection.
And, have you adjusted the bass and treble tone controls on the 1280db? Since they're now so close to you, based on your preference you can try cutting the bass so as not to overwhelm the mids and highs.
If you want a bit more control, try playing frequency sweeps. For example, for the 200-20hz, you ideally want each frequency to sound equally loud. But in reality, you'll find that certain frequencies will be louder and some will be softer. That's the room reflections making certain frequencies disproportionately loud, which muddy up the audio. For example you might find 130-135hz much louder. The bass tone control can help change the balance by reducing the bass frequencies but it's a rougher tool because it reduces a wider range of frequencies. For more precise adjustments, you will need EQ software. They can target a tighter range, for example, just reducing the volume for 130hz if the frequency is too loud from where you sit.
The YouTube channel has a lot of other frequency sweeps as well.
And of course, the 1280db will roll off somewhere below 50-60hz because they're not designed to play that low. This is where the subwoofer shows up.
Now, why does almost everyone recommends MR3? Because it's a pretty neutral speaker, definitely more neutral / balanced in frequencies than the 1280db. Would that justify the money spent though, compared to using the 1280db? May not be, because you may be perfectly content with the 1280db or your current pc speakers. Which was why I suggested to you to test the 1280db on your desk first.
And which was also why my next suggestion was, if you still want 'better' sound than your 1280db, put the money into a subwoofer like the T5s first. Because that fills in the missing 30-50hz that your speakers cannot provide you with.
Then finally if you really crave a more 'balanced' sound profile, that's when you can go for the MR3.