Sure, no problem...
I started this comparison with a demo at home of the Proac D2, D18, Spendor A5 (owned these already) and Harbeth M30; I chose the Harbeth. However, over time I reviewed my choice as my Harbeths weren't sounding quite open enough for me.
I then tried the other Harbeths (C7 and P3) for several months, buying them second hand, and it's clear they all have their own qualities. The C7 had a little more brightness but were less revealling and the brightness wasn't as natural as the M30, the M30 has a better, soft dome tweeter. The P3 are excellent, but would love these for more nearfield listening. Absolutely incredible for their size though. Really musical too.
After several months, the M30 proved to have a more sophisticated level of openness and realism, but they may not impress in the showroom as they aren't quite as bassy or bright. During these three months I also revisted the Proac D2 ( I actually bought some!) and demo'd the D1 also.
Every time I switched to the Proac D2 at home, I liked the clarity of the upper frequencies and the smooth mid range. However, over a few days I would start to notice vocals and mids becoming wispy and a little unrealistic. They are still lovely speakers and will suit more complex and loud music better (heavy rock for example) as they are knocked back a little in the mids, but going back to the Harbeths I would really enjoy the music all over again, natural, smooth, accurate etc.
It sounds like you won't like the D1 if you don't like the Tablette. For me, they were in between the D2 and Tablettes in sound style. D1s were harder and punchier than the D2, but with good clarity, and smoother than the Tablettes, which were too clinical for me, without authority or warmth. The harbeth P3 had more weight, warmth and realism than the D1 and tablette.
After some changes to my system - Added the Naim DAC to the Supernait, changed the Naim cable to tellurium Q Black, a good Wireworld optical lead, new Mac Mini (with low jitter) and stopped playing Mp3, and played FLAC instead, my Harbeth M30 came alive. I was basically suffering from a poor source and not ideally matched intermediates.
I'd be careful changing to the Proac, but horses for courses. Can you do a home demo? They are great in the showroom but I ended missing the Harbeth qualities. FWIW, even though my fave Harbeth is the M30 (after the Super HL5 which is too big for my room sadly) the P3 was my next favourite. They had amazing clarity, like the D1 but more music. It's because they are a sealed box and have a light bass, which helps them come to life in the upper frequencies, compared to the C7. Also, I would double check your C7 have room to breathe, otherwise you will lose the clairty and detail in bass and mids. Open frame stands, away from walls, decent listening height etc, I'm sure you're aware! Also, have you removed the covers? They open up a little, but depends on whether they suit your space like that. I like to hear them bare, but prefer the look of the covers on.
Hope that's useful and good luck with your choice. Will aim to check the post agaon soon, see how you get on!