Definitely a trail & error when it comes to piggies.
Even when I am a full-time stay home
GP parent, I am still learning from my piggies something new everyday, as well as other sources (this site, that site, everyone here, cousin who is a vet & FIL whos family owns a cow farm).
My bubbles nibbles (she has the excuse as a young pig) quite a bit from the start, she has improved so much & have cut back significantly now (she know my scent). While Yam-Yam never nips & my white abby very rarely does (only a couple of times when I am handling food). My FIL is the one to remind me that you never cower from a nip or the nip will go on... most time, I just think of bubble's nips as kisses, besides they really do not hurt (as a real bite will draw blood as sharp as their teeth is). I also will let my piggies smell my hand all the time to let them get used to me.
Piggies do have different personalities.
Bubbles is the "wild" one, the boldest, loudest, most bubbly of my pack. She is also the hardest to catch, the pig that does not like to stay still & the explorer of them all (yes she is the trouble maker). She is also the food hog, loves to eat & you see her always either near the food bowl or in it. She is a natural born leader that one, and I think will easily be top dog when she grows up.
My blue eyed abby is dubbed "diva queen". Coconut Pudding is her initial name (b/c she melts my heart), then tofu, snoopy (as per DH) & the latest mothball (no wonder she only respond to "Hi beautiful"). She is the scaty cat of the bunch & will scatter on cue on everything. She is also our family's "friendly" ghost, you can easily pick her up to pet but just spook easy (so easily spooked that she peed on me 1 time when I first got her). She is more of a follower.
My top dog, Bubble's mom Yam-Yam. She is a sweet potato that one, is a big time lap pig that she will even jump unto your lap during lap time. She is the top dog now as she is the oldest... she is also very steadfast, can be a laid back pig (like don't trouble me if it isn't serious type). She could easily be a "show" pig not so much she is "showable" but on her demeanor that she is so well behaved & will literally be very "still" when you put her a certain way (then you can pet her, groom her, do her nails etc.). Easily the most well mannered pig of the whole bunch (and she never pooped or peed on me once). She is a very dependable pig.
I know all my piggies love me as they always prefer to be with me (in the living room roaming free). They do not bite me & will chase me around (bubbles will, then others follow). They approach me fine, got so comfy they will play & hide under my skirt (I love long skirts). They wheek & order me around (like hey more food slave!). They will mutter & complain & whine in my arms. Most respected is that they actually will hold their pee (not good for piggies to hold their pee long as they do get UTI so every 15-20 mins tops before break recommended), like when I let them go on break after laptime, they will use potty immediately but not on me.
P.S. at the moment now writing this, they are all behind me making "oinking" noises & dashing around my furnitures like a crazy nut, with a "pop-corning" here & there.
Oops, bubbles just went back to his piggy home "sulking" b/c I just caught him trying to go up the bed-room steps with a stern "No!" (yikes that little rascal!).