Although I have enough of them that there is a potential for them to couple up and start pairing, until they actually do so I shall refer to these knives as paring knives...
Like most here my usage of them is limited; for peeling I usually opt for a speed peeler, and most other things work just as well with a gyuto, so I usually don't
bother to grab one because the time saved by using a more optimal knife is negated by the time spent cleaning another knife. There's also a bit of a chicken & egg problem going on; I don't use them much, partially because I don't have one that I absolutely love using, and because I don't use them much I'm unwilling to really invest in them...
What I do use them for:
-coring strawberries
-trimming potatoes (pits and ugly spots; usually I prefer to keep as much of the peel as I can)
-peeling when I actually care about oxidation (most of my speed peelers don't exactly have a finely finished edge, so there's more bruising of the product)
Contrary to most I don't really use them for opening packages or cutting butter; I have a few ultracheap 4-for-1 euro ones for that which I don't mind tossing in the sink from 3 meters away and throwing in the dishwasher...
I've tried a whole bunch... all having different pros and cons but not a single one that's 'perfect' so far.
My observations - preferences so far:
-I vastly prefer them to be on the shorter end of the scale; <10 cm. That basically takes almost all Japanese petties off the table.
-I vastly prefer low blade height since it makes the knives more nimble and makes coring / taking out pits in a rotating fashion far easier. This takes the majority of Japanese paring knives off the table as well.
-I prefer an exposed heel for sharpening
-I prefer low weight; I don't see any real benefit to having a more weighty paring knife
-Similarly I prefer really thin laserish blades; less resistance and the blades are too small to gain any benefit from fancy geometries or stiffer blades.
-I prefer a mittelspitz / office knife / spear point kind of blade shape... Sheepsfoot is alright for peeling but sucks for paring / trimming / coring. I haven't the faintest clue how I'd sharpen the scythe shaped ones, so I have stayed away from those.
-A lot of the paring knives, especially those trying to be fancier, are overbuilt, making them too thick, stiff, cumbersome, etc. Better to keep it thin light and simple instead.
-Slight preference for a good quality (semi-stainless) if you care about versatility; they are often used on fruits and often on-and-off while prepping.
-Virtually all handles of paring knives I've tried so far are too small for me and it's my main gripe about them.
My most liked one is a cheap Herder mittelspitz; arguably what I want is something like that, but with a handle twice as big.