The KH80 is a great suggestion but pricey. We install many of these at work. my opinions on these.
Adam T5V you either love it or you don't. Not my personal favorite but many people love the ribbon tweeter. YMMV.
iLoud MTM larger than you think and height is close to the LP6. About 2 inches narrower and not as deep but its shape keeps it from appearing as big as they are.
Iloud Micro is a good choice for small monitors
IN-UNF I have on my desk and love the midrange of that coax driver. Really nice imaging and soundstage. Bass can be a little tough to get positioned well. On my desk I found it works better with the bass module upright. When placed on the desk with monitor on top It was al ittle too bassy. YMMV.
LP-UNF We are due to get a shipment in the next week. I will be comparing them the the Kef LSX II and the IN-UNF both of which I have in my house. I have a feeling these will be a tremendous value for the price as are most of Kali's products. I'm curious to see if they beat the LSX II for sound. It might seem a price mismatch but the Kef has adavantages of being more feature rich.
LSR-305 A good speaker not as nice as the LP-6 for sound but still very good for the price and not as big as the LP6
IN5 - Definitely a step up from the LP-6 but not quite as wide but is taller and deeper so might be more intrusive for your setup.