I'm owner of 3 cameras. EM10.2 , EM5.2 and GX9.
Although I love all 3, I end up using 10.2 because of its size portability. For my video channel i use my GX9 and perhaps for demanding photos because of the newer sesonor. I really like the EM5.2 but it is covered by 10.2 unless it has bad weather I carry it with me due to waterproofing.
I also have 3 primes 17, 25, 45 and 3 zooms 12-32, 12-50 and 40-150.
I use the primes more and more lately because of the result that satisfies me.
The ranking order for me is
Keep these IF they match your most used focal lengths:
17 1.8 Laowa is the best for city and countryside and good for video because of MF
45 1.8 fantastic IQ it's more and more useful for me.
The question that arises is the following.
I want to buy a 12-45 pro zoom and I want to sell some of what I have to finance it.
what would you do in my place?
First, check your EXIF data - find out which focal lengths you frequent the most. Then buy a lens that covers those focal lengths.
Keep the Laowa and the 45/1.8.
Sell everything else. That'll give you about 1200 Euro.
I'd then consider getting the OMD EM10 IV ($600 US body only) and the 12-45/4 ($550); both on Amazon. Buy them used and have money left over for extra batteries, powerbank, SD cards, bag, tripod, etc.
The 10 IV is the latest in the line.
Same size as your M10 II, same weight. The 10 IV has the latest Oly colour science and ISO performance; better IBIS and I think it shoots 4k without a crop. It'll play nicely with the 12-45 and the 45/1.8. I'm sure the Laowa would be happy too.
Have fun and let us know what you decided!